Because it's possible that you'll die without warning.
So the best would be apostatizing and reconverting daily/weekly

So at worst you'll have a day or a week of accumulated sins ^_^
If one apostatizes, one is held responsible for all missed fara'id as well as all sins committed during the length of the apostasy. So you'd have all those prayers to make up, fasting, and blah blah, plus the burden of all that delicious bacon on your soul.