There are three sounds in both "ask" and "ax."

So it isn't laziness. It's a reversal of the order of the sounds. This is called "metathesis."

Oxford shows similar forms in use since Old English (before 900 AD). Here's a good example from the Coverdale Bible of 1535:

"Axe and it shall be given you."

(The first published English translation of the Old and New Testaments, predecessor of King James Version.)