Why athletes (and cats) stretch often.
Over time, as we build our muscles, strength, and/or get older, if we don't stretch regularly then our muscles can shorten and become tight. Range of motion will decrease. This is normal. You should stretch every day, or at least as often as you workout. It takes years for muscles to tighten and restrict our ability to move comfortably, so it will take some time to correct limited movement, you will need to stick to your stretching to benefit. Treat your body the same way an athlete does, get into that mindset. How often are you working out? Think about adding 20 minutes of stretching (or more) at the end of each training session, or somewhere else in your day. If you don't know how to stretch your body, talk to a physiotherapist or yoga friend – or you could study the neighbours cat ;-).