Also every time you start a game the mobs are random generated so you can get some freakishly hard shit or less freakishly hard shit. Generally people would fish for favorable greater rifts (abandon and start a new one) to make or get higher up the ladder. It's not really necessary to do unless you're at the top already where it's really cut throat.
and wouldnt that create a ton of lag of ppl were just generating games and abandoning them quick? increasing server loads is d3 ever laggy or have queues?
Nah it doesn't cause any lag. Rifts and greater rifts are generated inside a game. It's just like doing a dungeon in warcraft or any mmo. But to start a rift everyone in party requires a key so you can't just abandon and start over infinitely.
i dont know man im not convinced yet blizzard games are a trap man with their fuckin expansion packs every three months you end up paying like 2-4x the price of a regular game