What are the major causes for conflicts between colleagues?

1. Jealousy (Main cause)
2. Unpredictable policies
3. Different personal values
4. Perceptions

I agree with my colleague patel

I agree with Divyesh Patel, and add the below:

- The lack of communication is a key reason for all conflicts.

- Thefting work.

- Criticizing someone's work negatively (like mocking)

- Reporting to the manager the bad side of what an employee did (cutting the whole story to bad acts only)

Work division, Salary raise, promotions, cheating

Agree with Divyesh Patel, and  would like to add:

- Management weakness.

- Regulations not properly communicated and applied.

- Absent of Management prestige.

- Lack of cooperation and spirit of team work.

- Backbiting and Gossiping.

Conflict of interests.

Lack of good management with tasks and evaluations.

Positions and incomes.

Personal relations.

Backstabbing.

Gossiping.

1) one colleague does more than the other.

2) The one that works hard is often underpaid.

3) Lack of following instructions and maintaining the team environment.

4) Using race and place of origin as excuse to underestimate each others experiences and knowledge.

5) ETHICS! Some have it and others don't as well as morals.

6) Snitching and telling tales to management (girlish and childish but it is happening!)

7) Jealousy. 

8) Bad management who only takes sides and not looking at the whole picture.

9) Lack of conflict resolution skills.

Just to name a few.

1. Performance competition.

2. Personal clash.

3. Cultural dissimilarities.

4. Lack of trust.

agree with Divyesh Patel  

1. Different personalities and opinions
2. Lack of the ability to separate the practical and personal side
3. Work pressure

I agree that Jealousy is the main reason of the conflict among colleagues. Another reason as well is "Treatment from the management, rank and files employee should be treated fairly as well.