How to retain employees

From the day businesses has started, retaining employees have been the MOST talked about topic.

I see there are 2 aspect, why employees leave any company, which are as follows:
1) Monetary aspect
2) Monotonous aspect

1) Monetary aspect - everybody works for money, though this is important but still can be manageable if you are able to provide reasonable/fair amount of money to the employees.

2) Monotonous aspect - this is very very important aspect even bigger than the monetary aspect. Nobody wants to do the same thing over n over again thru out his/her life. How we can overcome this aspect, is as follows:-

a) Work Environment - this plays very vital role in retaining employees, friendlier the work environment, bigger the success of retaining employees. Treat your employees as if they are your friends, talk to them nicely, have parties at regular interval of time

b) Learning and implementing New things - this is motivational factor, when you tell your employees to learn new things which they will be implementing in the company, Employees feel their importance in the company and take great enthusiasm at work. Learning always give a new approach to your personal growth. Like said in the beginning nobody wants to keep on doing the same thing for forever, everybody wants to learn new things and when you give them the liberty to implement what they have learnt, you are giving them a sense of belongingness to the company.

I have interviewed so many candidates and almost everybody said that they dont see any scope for their growth in their previous company so they want to leave. In other words it had become so monotonous for the employees that finally they have to take this drastic step of leaving the company.

If we take care of these things, i'm sure any company will have less iteration and have more retention.