$$$ versions have few cons: 1. It is a decision point so requires reselling at every new version. 2. Old Versions must now be maintained for n years. 3. Feat

$$$ versions have few cons: 1. It is a decision point so requires reselling at every new version. 2. Old Versions must now be maintained for n years. 3. Features and sometimes bugfixes) are now kept on hold to bundle to make a big bang version release. 4. Multiple devices now add additional decision point, should you buy and iPad pro version of the app and a mobile one. Value of these would vary for users. With a subscription model: companies can reduce the maintenance window, have a 3 months release cycle, support multiple devices and have only one decision point for the user am I making enough to justify $ / month.