Yep, on the women's side it's very unpredictable.
This unpredictable women Tennis actually lost me lol
There was a time for Hingis, Henin, Williams sister. They performed consistently.
These days I only know few faces: Bencic, Andreescu, Osaka and few more :-P
LOL, those where the golden years in the last 90's and early 2000's.. Martina Hingis spend 200++ weeks as number one women's player.You can add to this list, Kim Clijster, Lindsay Davenport. But now, it's totally different, we have like different winners every tournament. LOL.
So it's really hard to bet on them and you could really lost along the way.
. Another case is Stephens Sloane, 2017 US Open winner, peaked at number 3, unfortunately we haven't heard about her since then and she was out of the top 10 this year.