Fights happen when we each benefit from opposite conflicting things.
If salesguys are selling your product at a loss, maybe it’s because their commission is made on gross sales, not profit. Set their commission to profit so they’ll help increase profits.
If the IT department isn’t fixing system glitches, maybe it’s because they get more respect and recognition every time they save the day and fix a problem, but no recognition when the computers run smoothly. Work with them to keep raising their standards of excellence, recognize them for success, and everyone will benefit.