Please leave the destination. Many times you do your research, plan your route (or not) locate the destination (and set it), then do something else with the phone before finally heading out and using Osmand.
If you make the app cancel your destination, all the work you did previously is cancelled, now you have to start all over. This makes the program pretty much useless.
There is already a menu button called "clear destination". What is wrong with leaving that the way it is?
Example of why not to cancel destination: right now I'm staying in a hotel in China. It is not on the map (not even in POI), the road to the hotel is not on the map. So first day outside I had the GPS find my position, and marked it as "destination. Now everyday (already a week) when I go out I can go everywhere, find my way back easy either walking or by bus (bus routes are not mapped, so except for some Chinese descriptions of neighbourhoods it is impossible to find out which bus to take). When the bus gets anywhere close to my "destination" I get of and walk towards it. I can use the phone for e-mails, games, pull out the battery (to reset it) or turn it off when I need to, and when I need the map again, my "destination" is still there.
I can think about similar situations when camping, hunting, hiking, biking. Mark your campsite, vehicle or parking spot as "destination" and it will always be there. No more getting lost, even when turning the phone off to save battery power. Leaving the "destination" marked can be a life saving feature.
Many people get lost in the mountains close to where I live, often with tragic results. There is no cell phone coverage there (not even in the national parks with 1.5 million visitors a year!). Having a program like Osmand can get you out, even if you have to stay overnight on the mountain.