Where I work, we can choose what we work on, as long as it's one of the backlog tickets the product owner wants done for the next release. The way they are for

Where I work, we can choose what we work on, as long as it's one of the backlog tickets the product owner wants done for the next release. The way they are formulated means there is very little room for solving hard problems (of the type that could result in fifty tickets not being necessary anymore), let alone making prototypes for things if they aren't guaranteed to releasable results for any of the tickets.