In viticulture it is known that even if you take the best vine from your vineyard, no matter how much awards it has already received, and put it in a vineyard someplace else, you will not get the same results. I think the clearest example is the stark difference between the wines made on the left and right banks of Bordeaux. Every place has a different microclimate and a different soil, meaning that the vines will end up acting a bit differently.

Similarly, in your organization you might have employees who are not put in the best environment possible for them, resulting, to continue the analogy metaphorically, in poor vintages. Personally, I believe that most organizations should hire more juniors than they tend to, and invest more time in their personal training. Yet too often I come across developers that are still effectively juniors in their positions, even after several years.

Assuming that when you first hired them you weren’t counting on having them remain juniors for years, the fault is at least partially on you as the leader. Maybe you haven’t provided enough feedback, maybe you didn’t make sure to devote enough mentoring, or maybe the person should’ve been moved or even fired. And still, the onus is on you to make sure the organization as a whole keeps growing and learning. Unless you have a division that’s intended for entry-level talent, you can’t afford any Peter Pan employees. As the percentage of sticky juniors increase it will become harder to manage.

My rule of thumb is that an employee should “level up” roughly every 2-3 years, the lower of the range for startups and the higher for bigger organizations. So an employee that is a junior after 3-4 years is lagging, an employee that made the leap within a year is ahead of the curve.

If you’ve never given this matter thought, I recommend sitting down and going through the exercise to get a feeling of your “Peter Pan Count.” I even set up a worksheet that you can duplicate and work on. I don’t like being pro Captain Hook, but sometimes you have to realize the clock’s ticking.