This song is about the feelings of guilt that frontman Corey Taylor felt as part of the grieving process following the death of bassist and founder member Paul Gray. He explained to Kerrang!: "Lech is one of the other tunes talking about the guilt in your guts, and just taking a look at yourself, and basically beating yourself up for having these very human feelings."
"In the grief process you can get angry at himself, and you can also get angry at the person that you lost – this person that you love so much – and when you lose them you get really angry, whether it's about their choices on the fact that you couldn't help them, and is a certain amount of survivor's guilt that comes with that," he continued. "Why is he gone and not me? It's an amalgam of just outrageous, just insane grief that really drives you into a bunch of different crazy positions, and Lech is about that."
"And 'Lech' refers to the word 'lecherous,'" he added. "It lets you feel like you're a bad person, and you have to fight your way through that, and it's a long process, but once you cut them out the other side of it you feel a lot better for it."