Reason why to not cut your griptape while on your board
My friend broke his board one day.
After further examination by me, I found that it broke exactly on a line he cut on his griptape.
He cut a line through his grip to accomodate a sticker.
As you can see on the picture below, the deep cut in the deck weakened that part and it cracked right along the line
To sum it all up, do not cut your griptape while it is on your deck.