For me, if I show a photo asking for specific suggestions on what to fix/add/take away, I want them. I want them before I continue to invest time and money. I may be asking when I'm tired of looking at the thing and need fresh eyes to offer input, and certainly want obvious mistakes pointed out if I show an unquilted top. Tell me before it's too late,please! If I don't ask, I'm probably aware of it, but you can still ask me nicely, "Did you intend to have such-an-such a block turned that way?" or something akin to it. It's like asking "Do I have broccoli in my teeth?" You sure hope you get an honest answer before you go to the DMV for your new license photo.
In this arena, where we are all quilters, we have "eyes" that generally know what to look for. So we spot our mistakes. I think it's okay to point them out to others. The quilt I most recently made (log cabin quilt for my sister) I had plenty of minor flaws in it (I fixed the major ones that made me mad as a hornet). But that was in NOvember and she loved it on first sight, unbound, on second sight, bound, and every time since. SHe texted me again just this week and said, "You really nailed it in the details of this quilt. I keep discovering all the ways you know me and what I what I love and you put them on the quilt." She does not notice mistakes (she's not a quilter so doesn't have critical eyes for stitching) and I won't point them out. I think when you point out mistakes to people who are clueless about your craft, it comes across as fishing for a compliment. I think on this board, we can give lavish compliments, knowing the work and love that goes into our craft, and we can offer (when asked ) constructive feedback.