Behind door No.1 I have the following offer: if I could guarantee that your NRL team made the top eight every season for the rest of your life, but never won a premiership during that time, would you be happy?

Think about it for a moment. You'd never win the wooden spoon. Your team would never be an embarrassment. You could go along to the football every weekend thinking your team could win.  The only trade-off is that you will never see your team run a victory lap on grand final day. Is that how you want your club to look and perform?

Now, behind door No.2, I have this offer: if I could guarantee your team would win just one premiership every 15 years, but for 12 of those 15years, it would languish in the bottom four on the ladder, would you be happy?

Think about it for a moment. You are guaranteed one grand final victory every 15 years, in exchange for accepting your team will be languishing at the bottom of the ladder for the majority of the years in between. I guarantee you one glorious year of delirious happiness, in exchange for 12 years of anguish and misery, being chided and laughed at by your workmates and neighbours.

Hmm ... Parramatta hasn't won a premiership since 1986. Before last year's grand final victory, South Sydney had not won a premiership since 1971.

Before 2010, the Dragons had not won a premiership since 1979. The Sharks have never won a premiership since entering the competition in 1967.

Since joining the NRL in 1995, the Warriors have threatened to take the prize on the couple of occasions but haven't opened their premiership account as yet. The poor old North Sydney Bears won the last of their two premierships in 1922 and were still seeking their third when they were removed from the NRL in 1999. Now they no longer exist. I guess there comes a point where some might consider door No.2 to have great appeal.

So, which scenario would you choose? If I know rugby league fans as well as I think I do, they will wait to see what prize I am offering behind door No.3.

Most fans want their team to be competitive every season, be in the top four several times over the course of a decade, win at least a couple of premierships during this time,  hang on to their favourite players no matter how old they get,and never fall to the bottom ofthe ladder where they are cannon fodder for all other teams in the competition.

Obviously that's not easy to do. And just as obviously, this is not a game show, and I can't promise any of the above situations.

The long-term management of an NRL playing roster is really becoming a science. In an era where it's accepted that a team's fortunes will rise and fall over time, it becomes important to manage, and sometimes even plan, your club's transition from one good period to the next.

What you don't need is to experience a rapid fall to the cellar and find yourself there for an extended period before you can climb the ladder again.

Over the past 15 years, we have witnessed wild fluctuations in the competitiveness of individual clubs as they ride a frustrating roller coaster of mixed fortunes.

Most clubs are able to get themselves in a position to challenge for a top-four position at least once or twice a decade. Some  are able to maintain this lofty position for several years on end. For others, though,  glory is but fleeting.

It appears that the window of opportunity for winning a premiership with a particular group of players is limited to maybe one or two seasons. If you miss your chance, it might be quite a while before you find yourself in that position again.

Some people seem to think this yo-yo dynamic of teams rising from the cellar to the penthouse and then falling back to the cellar again is good for the game.

I don't particularly like the fact that much of this "sharing of success" has been manufactured and artificially created through a restrictive salary cap model that punishes success and fails to reward good player development. But I think I've made this point before.

The one obvious thing though is that you can't be great forever. If you try to hold on to a successful era for too long, you run the very real risk of a swift and heavy fall to the cellar when it's done.

Manly are coming towards the end of an outstanding decade of excellence. Not for one minute am I suggesting they are out of the running for the 2015 season. If they can get their full complement of players back on the field in the next few weeks, there is still time for them to make a run for the finals.

If you can find form and gather momentum, it's not difficult to get on a  winning run in this competition, as teams such as  the Dragons and Broncos have shown in recent times. However, from a long-term perspective, it is quite obvious the Sea Eagles need to embark on a rejuvenation program for their playing roster over the next couple of years to produce the club's next great era.

The problem is that, in hindsight, they might have been better off implementing this program a couple of years ago so the fall from grace would be not as swift, nor as great.

In an age of salary cap restrictions and intense competition for player talent, it is truly an unbelievable performance for a club to remain premiership-competitive for 10years in a row as Manly have done. For the most part, they have been able to keep together a roster of tremendously talented players during this 10-year period.

Think about the number of great players who stuck together to wear that jersey and produce outstanding results for the Sea Eagles during the past decade or so: Jason King, Matt Ballin, Brent Kite, Anthony Watmough, Glenn Stewart, Jamie Lyon, Steve Matai and Brett Stewart have all been long-serving players during this unbelievably successful period in the club's history. Kieran Foran (132NRL games) and Daly Cherry-Evans (110 NRL games) joined the gang in more recent times. All these guys have contributed greatly to  a football culture and winning mentality that all Manly fans can be extremely proud of.

When things are going well, it is often hard to let go. Other clubs envy what Manly have been able to achieve. Most could only dream of the kind of glorious run this club has enjoyed over the past decade.

But nothing lasts forever.

There were signs late last year that cracks were beginning to form in the armour once made of steel. The team was highly competitive and in September it was still threatening to produce another grand final experience. However, some of the old warriors were starting to creak a little, as this long period of intense competition was beginning to take its toll.

Manly's start to the 2015 campaign has been dogged by player losses over the past two off-seasons, as well as injuries to several stars. For the first time in a long time, they are being forced to draw on player depth like never before. Unfortunately, it's not quite happening for them at the moment.

I've experienced this situation several times  during my career. You have a premiership-winning group that you want to keep together forever. You can bring one or two new players into the group and nothing much changes; the winning continues. But eventually it gets to a point where the great players are getting older. Rewards, recognition and contract values start to dominate the thinking. The team mentality and camaraderie are replaced by a new sense of individual entitlement.  Players start to sit in judgment of the coach rather than listening to what he has to say.

As the great players age, injuries start to occur more often and suddenly you turn around one day and there are a dozen new faces in your team. It's just not the same any more.

There comes a time when you need to leave the past where it is, in the past. Those days will always be glorious, always celebrated and always fondest in our memories.

The individuals will be recognised in the future Hall of Fame. The fans will remember them forever. But time moves on. Nothing, and no one, is bigger than the club.

The development of youth is always a priority. You always need to have young talented players coming through your system.

Hopefully one day you strike upon a talented and committed group of players who are prepared to stick together for a good period of time to give your club the success your fans desire.

If you are lucky enough to ever experience such a situation, you will learn what a glorious time it can be.

Every club needs to keep investing in its future.

• Follow LeagueHQ on Twitter
• Play Ultimate League