whoknows
If you don't want to fly "at the moment", why do you leave it running then?
Because I may want to fly "in a minute". There could be any number of reasons. Perhaps to avoid another start / stop cycle count during a short period on the ground, or doing lots of short trips and you need to get pax out the back, or maybe just landing and you need a pi55, perhaps to supervise hot refuelling, maybe having to load your own cargo net, perhaps you have an oil leak and you want to check for drips with the engine running, in fact any reason you may be landing somewhere for only 5 minutes or so and you need to get out, what's the point of shutting down if you don't have the time to wait before you can start up again? What if it won't start and you are on the beach at low tide?
I can only presume you also always shut down when you land, otherwise what's the purpose of landing eh?
I suppose I could ask you what's the reason for landing then if you don't shut down?