my personal experience with ninja:
1) avoid at all cost during peak season e.g. 10.10, 11.11, 12.12, black friday, before Christmas, NY, CNY, Hari Raya etc; arranging delivery regardless to home or collection point will be a big test on your patience and manners
2) all other times do your best to use collection points, any 24x7 7-11 or pick lockers should be your number 1 choice as some minimartts, maid agencies, pet shops have weird opening hours and those ninjas don't seem to bother checking opening hours, you may get the frustrating notice of ninja at collection point but failed delivery as point not in operation