Everything has to do with what range of hands you are putting the villain on. Therefore, when the 3rd tre comes, and you make quads, it's actually a green light to bet hard for a lot of reasons. You want mid pockets to follow you deep here before an overcard hits, and know that high pockets follow anyway. Your implied odds have naturally gone way up against any hand that will pay further in this pot after the last 3 drops. You get either a fold or a big committment from the opponent. You have to see this texture, and take advantage. Slowing down after the turn drops is -EV.

When deciding your course of action, never forget the low end of an opponents range, while taking care not to weigh your choice too heavily on that low range. Easier said than done sometimes. You get a feel for it. In this case your opponents entire range was at a pinnacle of confidence after the turn. That's the time to strike deep.