Why people leave my company?                                                                                                   Is there something I do wrong?                                                                                                             Is company not good enough to keep those people? Do we pay enough?

From my experience and observation, people leave from 3 main reasons                   (and many others).

Cultural fit
Some people are not fit with our company culture. We value growth, responsibility and independency.
We want people to be nice to others and be focused on results vs activities. Constant improvement is key for working with us. Unfortunately, not everyone feels the same way. Then it’s better to part our ways. One rotten apple can spoil whole basket.

Growth
Our company grows year on year not only in revenues but also in number of people who work here and in the number of projects that we do. All this brings new challenges, new problems and lot of changes. This also requires you to be flexible with your approach and your thinking. For some people it is difficult to keep up with the pace. They simply grow / develop slower than company grows. This still means, they can do great, in “slower” environment.

Capability
Sooner or later everyone reaches position where he/she uses his/her capabilities to the fullest. Should he/she be moved any higher or given more responsibility he/she would not be able to make it. I don’t tend to push people for more responsibility if they (or me) don’t feel they wouldn’t make it. I leave them on the current position where they can excel for some more time. How long? Until situation from point above will happen…