Did you ever feel that the BTVS Show jumped the shark Yes or No and Why?

kinda, yes. Twice in fact, if that’s possible.

• First when kid sister Dawn, the mystical, magical “key” was suddenly introduced with no explanation or backstory (which did, finally, come later). It was a gamble that paid off eventually though and Dawn became an important part of the Buffy mythology and an integral member of the show.
• Second, when all of the “potential” slayers were brought on in the last season. Although the ending was pretty close to perfect. Joss is a genius.

Some fans of the show would argue that Buffy jumped the shark in season 6 when (MASSIVE SPOILERS) the Scooby gang chose to resurrect Buffy after she sacrificed her life to save the world in the season 5 finale ‘The Gift’. There is a general opinion that Whedon had planned to finish the show after five seasons due to WB cancelling the show after 5 season and ‘BTVS’ (in it’s first five seasons at least) was about Buffy’s journey to adulthood and growing up show through her role as the slayer with the ‘The Gift’ showing her finally reaching the end of this journey. A lot of people disliked season 6 as they felt that the finale of season 5 would have been the perfect ending to Buffy, instead of dragging the show on with the much darker season 6 and slightly underwhelming season 7. Personally I don’t think Buffy jumped the shark. Whilst Season 6 and 7 are definitely problematic they fit into the foundation of the Buffyverse with their own highs (The musical episode, Tabula Rasa, Spike and Buffy’s relationship in season 7, Chosen) and their own lows (Kennedy, ‘whiny Dawn’, lack of structure in season 7). Compared to the rest of the show they are very different but without them we wouldn’t have our Buffy.

But more importantly, while I know a lot of fans don’t like the later seasons as much because of the darker tone, fewer metaphors, etc., “jumped the shark” really refers to a point at which a show has run out of new ideas and is just doing gimmicks and tropes, and that does not describe BtVS in any season.