Let's say someone posts a thread on this forum asking for a beta, explaining what their story is about and what they want. What makes you decide to message that writer -- or alternatively, not message them? (Assuming the story is question is in a genre you like and all that good stuff.)
Does the story have to be a certain level of "good"? Or is it the opposite -- do they have to have flaws you know how to fix? Do they have to be someone you already know?
Just wondering!
Wellll...
What makes me decide to beta is a combination of things that have nothing to do with the request and things that *do* have to do with the request.
First consideration is whether someone I know and respect is asking me. Closely behind is whether I have time to do it or not.
If the first is true, I will say yes, unless I really really don't have the time.
As far as looking for things to read in this part of the forum, though...well, I don't even look unless I have the time and inclination, generally, so we can discard that, although it's probably the single biggest factor...
Considerations after that:
1) How much I know of the poster and their writing from the site (not necessarily SYW excerpts or whatever; posts count) and how I feel about all that. I'm far less likely to read for an unknown entity than someone I'm at least a little familiar with.
2) The genre and market. I feel awkward and kinda scared about offering to beta MG or children's or something I'm equally unfamiliar with--even if the story sounds interesting, I'll often balk at offering, because I really haven't read anything for that age level since I was that age (with a few exceptions). Likewise, I'm not going to offer on something like erotica or other genres I don't read because I'd be useless.
3) The summary of the book, or link to excerpt on SYW, or some other thing that gives me a decent idea of what the book is like and a brief idea of writing style. I prefer to see a summary or query or something, so I can see if it appeals to me for whatever reason.
As far as whether the book is "good" or not...I really don't know that I could tell without reading the manuscript
But I like to see that the author has tried to learn to self-edit to some degree, and I like it if I know that they've received (and given) critique before, so forum participation really helps.
That's all just me though.