Vague or Wrong?

From my Daily Review of books and articles I have highlighted, provided by Readwise:

I’ll admit to being someone who has read Getting Things Done. I’ve also read The One Minute Manager, back when it was first popular and I was first trying to claw my way out of sales and into management. I don’t think I got much that was useful out of the earlier bestseller, but I suppose there were some valuable ideas in GTD. Even so, it reminds me a bit of the character Agnes Lowzier in the 1946 movie, The Big Sleep:

A half-smart guy, that's what I always draw. Never once a man who's smart all the way around the course. Never once.

This particular quote did stand out to me as an interesting idea. I guess there’s a place for pithy aphorisms. Seems like there’s probably some truth to the idea that it’s sometimes better to say something positive rather than to dither. I imagine it depends so much on the cost of being wrong, that the actual value of the idea is probably to focus people on that question. What’s the downside if I’m wrong?