Well Idk, I'm around 2500 MMR for aram, so I constantly see the same players. There was a very toxic guy on my team who would constantly sit in base an move his champ around to not get an AFK warning if he didn't feel like playing against certain team-comps/champions. So I was considering dodging when I saw that he was on my team.
In the end, I decided not to because our team was half decent, so I was guessing that he wouldn't afk. But then, in the last 2 seconds someone dodged the game, and I thought to my self "If I had dodged earlier, the one getting the time penalty would be me and not him, so clearly, the earlier you dodge, the worse. (if you're going to)
Personally, I very rarely dodge aram, maybe like one in 200 games, because I know that there is a very high chance that someone else is going to "do the dodging for me" so to speak, and if no one dodges, that's fine too, sometimes your team comp will look bad in champ select, but then theirs is worse, or maybe one of your "bad" champions counters one of their seemingly good champions.
But a big reason why I usually never dodge is because It's not very fun to sit in que for 20 minutes trying to find other high mmr players along with the 15 minute dodge timer.