Discounts as a tool, not a habit
A discount used on purpose moves a deal. A discount used by reflex erodes the business.
Tie discounts to something the customer gives up
Off-season scheduling, prepayment, larger scope. Free discounts (no concession in return) teach customers to always ask.
Cap them in writing
No employee discounts the price more than X%. No same-day discounts. Without written limits, discounting drifts. With them, it's controlled.
Track every discount as a P&L line
Total discounts given per quarter is a real number to look at. Most owners are shocked by what it adds up to.
Take your version of this question further
This is one operator-tested angle on the question. Your shop, your size, your trade, and your team change the answer. Ask your specific version inside Ask a Shop Owner to get a response grounded in how owners like you actually handled it.