The idea of a
poker site, which is much softer than other sites, is mostly an illusion. If such a site excisted, then more good players would start playing there, and eventually the site would not be soft anymore. So in general for a soft site or even soft games to exist, they typically need to be associated with some sort of drawback, that might keep good players away.
The most obvious example could be a geographically limited site. But unless you live in the area, where that site operate, you cant play there, so for most people its irrelevant if the site is soft or not. For instance I cant just choose to play on PokerStars PA rather than PokerStars.com, even if I wanted to.
Another factor, which can turn good players off, is low volume. But obviously its a tradeoff, because if volume is low, games might be soft, but your hourly winrate might still be low, because you need to wait to get into games. This can especially be an issue for SnG players. Some will also argue, that sites, which dont allow HUDs, tend to be softer. That might be true, but then you can also not take advantage of using a HUD. So maybe its not any easier for you to win, even though the games are in theory softer.
The ultimate inconvenience is live poker, which is why, a 1/2$ live cash game is usually massively softer than even a 25c/50c online game. But again your hourly winrate might not be higher, because you spend time and money on transportation, maybe you buy expensive food and drinks in the casino, and you can only play 25-30
hands per hour, whereas online you can easily play 10 times that number.
