He Regularly Cancels Plans
Things happen and plans have to change every now and then, it’s normal and not a big deal. However, if he is always canceling the plans he’s made with you, especially at the last minute, it’s a sign that he doesn’t consider your feelings.
He could also be seeing someone else or putting time with his friends before you. Whatever the reason is, you certainly don’t need to be sitting around waiting or continuing to make plans with a man who doesn’t have the courtesy to treat you with some respect.