Because these things are nothing to do with drones, they are basic principles of photography which you ought to have at least a grasp of if you go out and spend hundreds of whatever currency on a flying camera.
A question was asked and got a realistic, honest answer. Off several people.
If you don't want to hear an honest, correct, answer than why ask the question?
Or would you rather people just lie about basic physics and photography to make you feel better?
This is absolute basic photography, nothing to do with drones. Its something 5 seconds of google could have yielded as well.
Some people seem to be getting very snowflakey on here.
Did you mum not teach you how that if you have nothing nice to say, don't say it...?
Bored of you know, I'm off to converse with real.people.