Launching an app is a poor metric, as there are all manner of use-external reasons why an app may be started or stopped. A timer? Perhaps, but my perception is that most folks hate feeling "on the clock". Maybe per-day, or a days-per-month ladder of some sort, to relax that feeling? Seems more complicated for the end-user and for Adobe with the only real upside for very casual users.
To some extent, a monthly subscription seems to strike a balance between an incremental usage fee (aka "use") and avoiding the complexity and psychology of timed usage.
Launching an app is a poor metric, as there are all manner of use-external reasons why an app may be started or stopped. A timer? Perhaps, but my perception is that most folks hate feeling "on the clock". Maybe per-day, or a days-per-month ladder of some sort, to relax that feeling? Seems more complicated for the end-user and for Adobe with the only real upside for very casual users.
To some extent, a monthly subscription seems to strike a balance between an incremental usage fee (aka "use") and avoiding the complexity and psychology of timed usage.