You're right on the money.
I, too, scan the ads daily.
Let's say you start with 1000 ads.
Discount the 15 & 16 year-olds - now you're down to 850.
If you like heavy metal, then there are about 650 ads left.
If you're like me, and you like anything but heavy metal (punk, rap, et. al. . . .) then you have maybe 200 ads left.
Discount those who are WAY too far away - now you have 40 ads.
Of those 40 - 15 won't reply.
Of the 25 who reply - for one reason or another, - maybe you'll actually meet 12.
Of those 12, 1 will do drugs, or party constantly. 11 to go.
3 are headed in the wrong musical direction, style-wise. 8 to go.
1 canceled on your first meeting, and post-poned the 2nd. 7 to go.
2 lied about their ability. 5 to go.
1 of them is a real creep. 4 to go.
1 was just accepted in another band which he'd been trying to get into for the last 2 months. 3 to go.
1 is a control fresk. 2 to go
1 has issues with a girlfriend/boyfriend. 1 to go.
I think you might want to adjust some of those figures a bit, but - man, you better hope that the one guy/girl who is left is dedicated!