Once they have you signed up at typically a huge cost for a site that is leased from them and not owned by you, there is constant pressure to upgrade to their latest version, and as of late a massive increases in hosting fees. Also huge rates for programming changes. They know how reluctant their customers are to walk away from costly customisations or to spend time on transferring site content and leads to a new platform, so they assume they have you by the balls. That's not going to work on me though. Buyer beware!