When users are filling in a form, they often want to focus on the task, get it done quickly and move on to their primary task - making a purchase or registering for a service.
The best way to solve a specialized task is often to write one or two utilities and a bit of glue to tie them together, rather than writing a single program to solve the whole thing.
On these systems, threads that perform time-consuming non-blocking computations can tie up a CPU for extended periods, decreasing the responsiveness of an application.
The private construction of a whole new city, Lavasa, has been halted over the brazen flouting of planning rules, presumably with the connivance of politicians.