An example of a break in is a robbery of a store.
An example of break in is the first month of driving a new car.
There was a break-in at the shop; everything was taken.
They should not require any sort of "break-in" period.
Do you think this was a random break in?
He didn't even bother to report this latest break-in.
The tips wear down, and they become flimsy and will sometimes even break in half depending on how hard you play.