Over time your door may become misaligned. This could be caused by the home settling, a remodel, wear, repeated use or being hard on the door the door. When the alignment is out your rollers may be hard to move the door or may make the door feel heavy. Also your lock may not be able to function properly because it no longer lines up correctly . When this happens we will come out and realign the door with the frame and lock so your door works as good as it should.