Why can't we use 'to' before 'not' in English language?

Question

1) He provided facility to do the task.------correct usage

2) He provided facility not to do the task-----correct usage

3) He provided facility to not do the task------wrong usage.

We use the second one for the negative sense of the first. But

Answer 1

because it just sounds better. Why can't we say 'gooder'? or 'more good'?

Answer 2

You're not supposed to split an infinitive.  "To do" is an infinitive.  To put something between the "to" and "do" is incorrect usage.  This rule has actually changed in the last few years.  Splitting an infinitive is not seen as incorrect as it once was.

Answer 3

because it does not sound to much better

because it does to not to sound to much to better.