The filament heat cycles, is also why I hate seeing people turn taxi light off when stopped, then on again, off again etc if moving in a queue. Just wastes good money for no benefit. Who cares if the taxi light stays on while you are stationary?
It is in my OM-B that the taxi light has a max of 10 minutes when stopped due to overheating. So it should be switched off when stopping, latest after 10 minutes. I have wondered about this making sense, but then I really don't care. They want me to do it, I'll do it!
Nic