Why would you assume that buying software gives you the right to free upgrades as new OS versions are released? Traditionally when you 'buy' it gives you acces

Why would you assume that buying software gives you the right to free upgrades as new OS versions are released? Traditionally when you 'buy' it gives you access to upgrades and support for a period of time. For me, that is much preferable, especially compared to a model like creative cloud, which only allows cancellations of the subscription once per year, with no refunds.