MCImes wrote: "Difficulty finding boats" is also a common response, but I'll lump that in with Cost of Equipment, because you can always find a new boat if you have the $.
As I was one of the 'Difficulty finding boats'-people, I could share some thoughts on that issue.
Money certainly helps, but it's more to it that that. When I began (the situation is a little bit better now), there weren't many brands available for trying and/or buying in my home area at all. You could go on a trip abroad of course, but that does not just cost extra money, it also "costs" extra time and effort.
The other problem is that, while I do admit there's many models I haven't tried, it seems to me that even worldwide, the selection of skis for anybody who is not a big guy with narrow hips is quite bad.
Lets start with boat volume: I have met one ski-paddling woman. She was sitting in the smallest ski from the Nelo Ocean ski series - the M. Even though it was the smallest, it was clearly a bit too big for her. And we see the same from other manufacturers. Epic's smallest ski, the V10 L, is made for people around 75 kg. What is a, say, 50 kg person meant to paddle? (This is obviously a problem not only for women, but also teenagers (of both sexes) - in case we wanted to recruit younger paddlers)
And then there's the hip width issue: When I began looking for a ski, I could easily find skis that were quite suitable for me volume-wise*. Even though I'm a fairly big guy (varying between 95 and 100 kg), most skis that aren't specifically made for smaller persons, are, volumewise, more or less perfect for me. But very few have wide enough seats. (Are people at the same weight as me, but narrower hips really _that_ common? Do I really have a _that_ unusually fat ass?) Given that women tend to have a bit wider hips for their body size than men, I can easily imagine that many women find that most surfskis are both too big (volumewise) and too small (seat-widthwise) at the same time.
* Actually, not even that was that easy, but those boats I could lay may hands on, were usually OK volumewise