The Cheating DM: Player Death

Ok so we've established my cheating ways. How do I justify player death? The short answer is mostly I can't. I haven't killed a PC in the longest time. There actually have been complaints. Came very close this week thou, critical hit on Stone Mage put him 1 hp from death. It's something I've grown so soft on. I almost always reserve PC death to poor playing and very special boss encounters (That I have completely stated out) The 21 yr old me would be MYSTIFIED by the games I run today. I am planning on bringing back the "soirit a littel thou. We'll all see if I pull the trigger on this.