YES I **** this too.. it makes websites like mine look bad, or at least people more weary to join solo girl websites because they've been burned in the past. Another version of a website that doesn't update is websites that recycle their content.. they take down the old stuff, only letting you view so many pages of porn at a time, then eventually it gets posted as new stuff:/
There are ways you can look out for such a thing: Are there signs the actual girl is active on her website? Is there a blog that gets updated regularly, is she doing webcam shows on her website weekly, is there a calendar somewhere where you can see the next couple weeks/months of updates scheduled? And you can always ask a girl on Twitter too
(btw I update 6x a month.. just sayin