While a tape measure is a simple measurement tool known to most if not all people, there are certainly a few things you probably don’t know about your trusty measuring aid. We will discuss tape measure accuracy. Tape Measure Accuracy Almost all the tape measures do have a loose hook. Which is actually a good thing and doesn’t affect tape measure accuracy. Before you pick a hammer to fix that darn hook that keeps moving about whenever you’re taking a reading, know that this is not a flaw but a special design feature.