Why would it matter if you take 1 minute or 1 day? Either way, the baseline expectation of functionality is for state to persist from one page request to the next page request, no matter how short or long that interval happens to be, and some kind of local storage (typically a cookie) facilitates that for both cases equally. Is it just to replicate the experience of that for which an online cart is a metaphor: with a physical shopping cart, a store employee will empty it out if it's abandoned overnight unless you explicitly ask them to hold it?