The answer to 'why is my dimmer switch hot to touch' is that a hot dimmer switch is typically caused by an overloaded circuit or a faulty dimmer switch. When a dimmer switch is working properly, it should not get excessively hot to the touch.
Some common causes of a hot dimmer switch include having too many lights or fixtures connected to the circuit, using the wrong type of dimmer switch for the load, or a failing dimmer switch component. If the dimmer switch is hot, it's important to address the issue to prevent potential fire hazards or damage to the electrical system.