What is wrong with movies.?

why dont they add a prolouge and epilouge it makes every mover better for example jumangi and zutheru there basicly the same mvie execpt jumangi had a proluge and epilouge.And why do some movies that are based on true event have alternate ending's like paronormal activty having 3 endings with the original being the scariest and why cant the find katie is it that hard 2 find 1 possed girl shes possed she acts diffent thn other pleople.