it means that the cost of moving from X is too high (be it in terms of time, cost or lack of suitable alternatives). In the case of iCloud, for most people, it

it means that the cost of moving from X is too high (be it in terms of time, cost or lack of suitable alternatives). In the case of iCloud, for most people, it's probably a combination of convenience (no other tool is so well integrated with the OS) and cost (you can sorta replicate the combo of photos + files + vpn + fake emails, but it'll be more expensive and complex to maintain)