I am a complete noob to Bitcoin, and this question might seem obvious to some. But I can't seem to get my head around it. I read how the process of mining works - they select transactions, verify them, create a merkle tree, and then start creating nonces. I want to ask whether a miner can skip the part of verifying a transaction, and just take the transactions as they come, just add them and be done with it? That is, what part of the protocol prevents him from defuncting, in some sense?
Sorry if this is obvious.