Failure

After having my water main repaired just below the slab of my house I am scratching my head in wonder. How does a length of copper pipe that has been in place for over 16 years suddenly start leaking out of 2 pinhole sized openings? I guess there is an object lesson there somewhere. Hundreds of feet of pipe controlling the flow of water throughout my house and for no discernable reason a pin hole sized forms flooding 2 rooms. As a percentage the integrity of the piping is probably 99.9999% but that is not good enough, only 100% integrity will suffice.