Why do some guys say things to you,but they dont do them?

Like this guy im like dating (not rlly sure) he saids little things to me and he dosnt mean them..like at school today before we went home hes like "i'll txt u" and I said "do u mean ittttt?" And he nodded his head and said "yeah." And its 8 pm snd he nver did..why do guyd do that? :/ its so annoying..he has done little things lke this before too..lke why even say it?