what is the 'mentality' of someone who leaves a heart on your post, but doesn't respond to it

i've had this a few times now from particular users, they leave a heart on my posts a few times recently but don't respond to my question? but i saw that this person responded to other posts recently and answered extensively? so what does this say about them? it's really annoying me now to be honest....i was thinking i should just block them so i don't have to keep putting up with their annoying behavior.