I have a client who intentionally offers up a bad idea when there's a lull in the conversation. This is a tactic she uses when she wants her team to generate new ideas to solve a problem and they're stuck.
She will make a suggestion that clearly won't work. Then her team will start talking about why it's a bad idea. This sparks questions they ponder together, which leads to new ideas being generated.
Until she offers a bad idea, people are too afraid to ideate out loud. They censor themselves and hold back. But once the boss makes a suggestion that's clearly got some significant holes in it, others feel less worried about how they'll appear.
Her tactic removes imagined barriers. People are less afraid of appearing stupid or ill-informed. They release attachment to their worth being tied to the quality of their ideas. And their focus shifts onto doing what's best as a team.
In this instance, the good thing about bad ideas is that they get people talking like never before. And once people start talking more openly, they're able to ideate viable solutions instead of staying stuck in fear of sharing.