platform update problems - why on a Friday and why so many bugs every time?

platform update problems - why on a Friday and why so many bugs every time?

Why do these updates cause so many problems and break so many features so frequently?

Why is there not thorough testing done using multiple browsers??

Why do the updates typically get rolled out on a Friday evening, thus leaving things broken on the weekend when I am usually working on our business's apps in preparation for the upcoming working week???

Why...why...why..........??!!!