Some guy called me bad but wouldn't really explain why

Just had a ranked game where our jungler deliberately fed the entire game and we lost horribly, but that's not the point. The person I was laning against claimed to be a past season(s) platinum. He played twitch, I played vayne. I harassed him in lane and, to a slight extent, denied farm. I was only able to kill their support once in the game during the laning phase.

After the loss and my bitching to everyone about how my efforts meant nothing, he mentioned that I wasn't laning well at all. Something about procing my Q and trading when my support initiated. Pretty much the entire laning phase I had him backed up and hurt more than me because I harassed him a ton, and I outfarmed him. But after the game, he said that my outfarming him meant nothing and that I need to wait for my support to do something before I attacked at all. Does that make any sense to anyone? It sure doesn't to me. But of course, since he claimed to be in a higher division in seasons passed, I somewhat believed him. Could someone explain this to me? I thought I was supposed to harass the other adc in the lane and deny them farm if at all possible, not sit there and hope my support decides to do something.