Your employer will not forget that you wanted to resign. In the eyes of your employer, you are no longer a loyal employee. Employees whose loyalty is questionable generally don’t get promoted.
If there are lay-offs to be made in your department, you will be the first on the chopping block.
In the vast majority of cases where people accept counteroffers, they are fired, laid off, or looking for a new job within one year.
Accepting a counteroffer can harm your reputation and character. Your employer, your colleagues, and those who hear about your acceptance of a counteroffer may believe that you can be bought.
Your company probably has a schedule to which they adhere when raising an employee’s wages. The extra money given in your counteroffer may simply be an early advance on your next raise.
Your company may only keep you until they find a new employee who will do your job for less.
Unless your decision to resign was salary-based, the same issues that bothered you in the first place will probably come up again. Remember why you initially decided to resign.
You may lose the respect and acceptance of your colleagues when they hear that you threatened to resign.
If your employers are offering you more money, did they not value you enough beforehand to have given you a pay increase?
If you’ve handed in your resignation, you’ve already accepted an offer from another employer. By accepting a counteroffer, you are breaking your word to your new employer, and that doesn’t bode well for future relations with that company.