I have noticed a trend in some web series: The series is started by a very talented individual who does typically reviews of something (such as video games or movies). Because this person happens to be really talented and entertaining at it, they get a really big fanbase, and their videos start getting hundreds of thousands, if not even millions of views. In other words, they become internet celebrities.
With celebrity comes money. And with money comes higher production values to the videos. It usually starts with better recording equipment, ie. better cameras, microphones, editing software, lighting, and so on. But once those are top notch, and the money still keeps pouring in, the production values are increased in other ways. Such as props, costumes, sometimes even hired people to act as secondary characters. And, of course, more complex scripts.
And this is were sometimes the project starts falling apart. Or perhaps not falling apart per se, but the series starts becoming less interesting.
Being talented at sitting in front of the camera and making an interesting and entertaining review of something, does not automatically mean that you are talented at making a more complex scripted show with higher production values. A talented comedian is not necessarily a good director, producer and actor. Once a comedian starts making their own complex production, things can go downhill fast.
The result is not necessarily horrible. It can be watchable. But the charm is not there. The original talent is overwhelmed with too much "acting", too complex scripts, needlessly complex stories, and too many crappy props and effects. It often becomes a jumbled mess. And it changes too much what made the original series so enjoyable to watch. It's now a very different show. These people try to reach too high, and fall short, and in the process they end up simply hiding their own original talent, distracting themselves from what they are really good at.
These higher production values are usually completely unneeded. There's no reason to have them. They don't really add anything to the show. There is no need to change the original show to something different, to something that it is not.
Often these people do it because the love doing it. There's no question about that. However, their original charm and entertainment is lost in the process. Or, rather than "lost", more like hidden under all the needless cruft.
Two prominent examples of this are the Nostalgia Critic and the Angry Video Game Nerd (and his spinoff shows). Don't get me wrong: These shows are ok and somewhat enjoyable even with all the production values. However, at least in my books, much less so than in the past.
Doug Walker (ie. "Nostalgia Critic") is a very talented internet reviewer. His review videos are some of the best out there. However, I don't consider him a very talented scriptwriter, director and producer to make any other kind of show. I don't mean to say he's bad at it, but he's not very good at it either. I'm sorry, but he just isn't. His other types of show (and even the Nostalgia Critic episodes that veer too much away from the original idea) are not very good. This was clearly seen in the fiasco that was his "Demo Reel" show attempt, which was so universally panned by fans that he ended it short (especially since he ended Nostalgia Critic in order to make this project.) Unfortunately, it seems that he's obsessed with making that kind of shows because he's turning Nostalgia Critic into what's essentially Demo Reel. And his most "Demo Reel"-like Nostalgia Critic episodes (especially the ones where he doesn't even show any footage of the movie he's parodying) are really boring to watch.
He himself knows this perfectly well. He recently made a Nostalgia Critic episode that was pretty much a commentary on this very thing. (It was an episode where his Nostalgia Critic character temporarily wanted to go back to the good old days of just reviewing a movie solo, with no production values, no actors, just him and the camera. A past version of himself, now in the present, made direct comments on how his show has become something completely different, and that episodes are not even reviews anymore.) It's not like he's in denial. He's perfectly aware of the criticism, even to the point of parodying it. But so far it seems that he's not going to stop going in the wrong direction. I hope he does, but it isn't looking very good.
The yearly specials produced by Doug Walker and the site's other producers are another perfect example of this. Year after year the production values of the specials have gone up, and their entertainment quality and fan feedback have gone down. Ironically (or perhaps not), the special with by far the highest production values had by far the worst public reaction and feedback.
James Rolfe (ie "the AVGN") is quite similar in this regard. He made lots and lots of videos parodying and criticizing old bad video games, and he was really, really popular. After something like 50 videos, the production values creep started showing. Not a whole lot, but a bit. It was still quite enjoyable for another 50 episodes or so. Then he started making the AVGN movie, and the show was pretty much shoved aside, with individual episodes being made really rarely.
What's worse, the show has been toned down enormously. His shtick of the cursing angry nerd is but a shadow of its former self. It just isn't there anymore. The show really has gone completely downhill. He makes episodes very infrequently, and they feel half-assed. Like his heart is not in it anymore.
The "production values creep" can be seen even more strongly in some of his spinoff shows. Just watch the first episodes of "Board James", and the latest ones. The contrast is quite drastic. And the latest ones I find really boring. There just isn't that original charm anymore. (I actually didn't even watch his "Nightmare" board game episode but about half-way through. It was just too boring and uninteresting.)
Higher production values do not always ruin an online review show. There are examples of the contrary as well. However, they really require a special talent, and a good balance between the actual reviewing and the production values, in order to stop the latter from swamping the former. (One example that I can think of where this balance is good is he Angry Joe Show. For a perfect example, check his review of Alien Isolation.)