There are a number of reasons why an electric smoker could catch fire. One of the most common reasons is because of a short circuit. This happens when the electric current is interrupted and then flows through an unintended path. Another reason is that the heating element in the smoker malfunctions, and this can cause it to overheat.
Electric smokers are convenient to use because they don't require any kind of flame or gas source to work. They instead work by using electricity to heat up a metal rod that sits inside a cooking chamber. The rod gets hot enough that it heats up whatever meat you put on it and cooks it for you in just minutes.