Even heating: skillet thickness vs. electric element size
Electric oven spirals turn on and off continuously, and the temperature of coil depends on the ratio between periods of cooling and periods of heating.

Thicker skillets act as accumulators of heat, allowing smoother transitions between those periods. They heat up slower and cool off slower, thus making temperature more consistent.

Another voice for thicker frying pan bottoms is that it prevents them from warping as much – metal contracts and expands on temperature changes. Cheap pan will warp after a while and stop forming a good contact with electric stove spiral, resulting in uneven cooking.

Hope this answers your question.