All Dr Sam Beckett wanted was to return home. Throughout Quantum Leap's four-season run, he got to rewrite history for the better, bed more women than James Bond, and even have a face-to-face meeting with god, but normality was all he craved.
The fans rooted for Scott Bakula's character from episode one, so imagine their disappointment when the finale ended with a title card which read "Dr Sam Beckett never returned home"? No further explanation about his ultimate fate, nothing to justify the groundwork he'd put in or the hours viewers had invested. Nada.
That title card may as well have had a massive middle finger drawn on it.
There is an explanation for the show's abrupt end, but it doesn't vindicate Quantum Leap's showrunners. Apparently, the final episode was never written as a rounded conclusion because renewal for a fifth season was a possibility.
When the plug was pulled at the 11th hour, the studio had to improvise and that cursed title card was all they could come up with. Could they not at least have gone into some detail about what happened to Sam? Worst. Sendoff. Ever.