The worst retrospective I ever facilitated (and what I learned)

Story time. Two years ago, I facilitated a retro that went completely sideways.

Context: The team had just had a terrible sprint. Missed the goal, two devs had a public argument, and the PO was frustrated.

My mistake: I used a standard "What went well / What didn't" format. Within 5 minutes, it became a blame session. One person called out another directly. The PO piled on. I froze.

What I should have done:

1. **Set stronger working agreements** at the start

2. **Used a format that separates people from problems** (like the 4Ls or Starfish)

3. **Had a 1:1 with the feuding devs beforehand**

4. **Called a break** when things got heated instead of freezing

The silver lining: This experience made me a much better facilitator. Now I always assess team mood before choosing a retro format.

What's your retro horror story?