Avoid insecure managers.  High staff turnover is often an indication that promising  employees are leaving.

Insecure managers avoid hiring people whom they think can replace them, nor are they interested in delegation of responsibility or developing employee skills.  They are also tend to stifle good ideas, or present them as their own, and if mistakes occur they tend not to support those who report to them.

If you have an insecure manager try and find a position either within or without the corporation where you are reporting to someone who feels confident  in their abilities.  A confident manager will want to develop competent staff because this invariably produces superior results.  They will also want to develop  candidates capable of replacing  them when the opportunity for advancement presents itself.