This posture corrector, like others have said, is more of a reminder to sit correctly as opposed to a device that forces you into correct posture. Therefore, if you're feeling uncomfortable, you probably have the straps too tight, or you're slouching! This is great because then you're less likely to become dependent on it. But don't ignore its warm-up advice: start off with just 15-20 minutes, and then increase your wear gradually. It's surprisingly comfortable because the straps are so padded and soft. It reminds me of a backpack--without the actual backpack part.