Yes. Not to the extent of thinking a good series is now bad (*side eyes Jason*
), but it certainly sours the narrative. I don't like wasting two months enjoying a good series for the payoff to be a disappointment. In all honesty though I mainly use it as a way of determining how to rank series I enjoyed in almost equal measure. So, like 14 was great but Sam's the worst winner of any reality show ever and Helen and Ashleigh are the best BBUK F2 of all time - thus 15 goes ahead. Similarly had Hughie/Andy/Jackson won BB17, it would've easily been my favourite series since BB10...now idk if it's above 15.
So I do put a lot of weight on the winner of a series, not in the sense that 'BB6 is now crap because Makosi didn't win' but it certainly makes some series hard to look back on as fondly as some others.