On the other hand, Valve tends to treat bugs differently with Dota 2.

They have a test client in which a small group of players can test out new patches and find bugs. Recently when patch 6.87 was released, they practically skipped the test client and deployed it straight to the main client. The result was that there were all sorts of bugs in the game, but they worked really quickly to fix them so that after a few days, they were almost all gone. I think Valve's mentality is that it is more efficient for their large player base to beta test for them instead.

Also, there's been a few times when the game is literally unplayable for one or two hours because Valve pushed a random update.