1. Login to ESXi console
  2. Go to Host > Manage > System > Advance Settings
  3. Search "security"
  4. Select "Security.PasswordQualityControl"

5.   Action > Edit option

6.   Change value as you perfer. Example: retry=3 min=1,1,1,1,1

7.   Change password via Host > Manage > Security & Users > Users

8.   Change user's password.

9. Set "Security.PasswordQualityControl" back to default value.