Knowing how long people have been with the company gives a clue as to what is going on within the business. This is particularly true of the management committee. It will be implicit in the beliefs that people hold about their career prospects and options.
If for example, all of the members of the management committee have worked for the company for the whole of their career, then this will set expectations about what career choices and paths are available to your staff, and what works and what doesn't in terms of promotion within your business. If they've all been recruited into the role from a similar level in a different organisation, that can be equally telling.
Significantly, you should consider whether this has any impact on the company culture. Do staff talk about whether management comes up from the ranks or have been brought in from outside? Is this perceived to be right? Does it act as a motivator or de-motivator for staff?
This pattern can inform policies and processes for individual career paths through the business, and whatever form it takes, it is important to gauge how comfortable staff appear to be with the situation.
It is also imperative to assess whether or not this fits with the stated aims of the culture of the business. If not, you need to think about whether you should be challenging it or introducing new ideas. Consider what your role will be in influencing change and how you will introduce your proposals.
There is not normally a right or wrong length of service. But what is important is whether the current status quo fits with the direction of the business, or whether it is simply an accepted fact that nobody examines. You will often find that this is a paradigm that a company simply 'ends up with', rather than something that is either examined or planned for. And if this is the case in your organisation, does it need to be addressed?
Think about what other untested approaches and assumptions there may be in your organisation that could benefit from being examined. But if behaviours are very entrenched, don't just go bowling in with a new idea. Look very carefully at positioning both yourself and your function before challenging anything, and put together a detailed business case for why things need a shake-up before trying to tackle any long-held assumptions.