Thanks for asking the question.
There are many, but here are ten:
1.) Managers or leaders not communicating with employees
2.) Leaders not providing tools for two-way communication
3.) Improper screening of applicants
4.) Improper or no training for employees
5.) Not providing a good orientation for new employees
6.) Leaders not clarifying the direction of the business (goes back to communication)
7.) Poor or no customer service training
8.) Not understanding the needs of customers
9.) Poor communication with vendors
10.) Leaders afraid of leading for various reasons.
This list took me about one minute to complete. There are so many more, but most can be traced back to a lack of understanding some very simply fundamentals.
Have a productive day!