The answer to 'my ceiling fan won't turn on' is that there could be several common causes, including a tripped circuit breaker, a faulty wall switch, or an issue with the fan's internal wiring or motor. The symptoms may include the fan not responding when the wall switch is turned on, or the fan blades not spinning at all.
To troubleshoot, start by checking the circuit breaker to ensure it hasn't tripped. If the breaker is fine, then check the wall switch to make sure it's functioning properly. You can test the switch by using a voltage tester to check for power at the switch. If there's power but the fan still doesn't turn on, the issue may be with the fan's internal components, and you may need to call an electrician to diagnose and repair the problem.