Han described Bespin as being pretty far but they could make it. Perhaps whatever the other system is takes a lot more time (like needing to cross solar systems to make a jump to the next system, than crossing that system to make the next, and so on). And it would be system to system, not long jumps that can cross sectors of space. Meaning for Han and the Falcon, they might run out of fuel or food, or air even if Bespin was much farther.
Also allows Boba Fett to low key follow the Falcon, than when it is obvious they are going to Bespin, jump to Vader, and jump to Bespin, long before the Falcon can finish crossing they system to reach Cloud City.