When it comes to the creation of OVA's for any given series, they serve a number of purposes. They give additional background to the story, as if filling in holes to the plot or deal with 'that thing we forgot to mention.' They develop the personalities of the main characters, giving them new facets to consider. They introduce new characters for the remaining or next season. They develop new plot nuances, either to prepare the audience for those things to come or try out an idea they want to see in an episode which won't be considered part of the actual series (and you got to like some of those tweaks).
But, when evaluating the OVA with the series, there is that matter of 'fit.' Is there some consistency with the series that you can appreciate, or is it too freaking different? For example, I like the fit to the two OVA connected with Encouragement of Climb and the special which comes out shortly after the conclusion of a season of Non Non Biyori. But recently, I saw this OVA connected to Girls und Panzer. A 'wild west' episode? Where's the engaging tank battles? In this case ... way too freaking different.
There was a sense of fit to the three specials connected with Laid Back Camp ... and then there wasn't. The first two took place in the clubroom/storage closet. This would be background for the Room Camp series that would appear later. The first story was Chiaki and Aoi bewailing the tiny room their club was assigned ... while reading a camping catalog. The prices of camping gear inspire a quest for 'hobo-chic' using clutter from the storage area. Thank goodness, they found that 980 yen tent on special. The second episode introduced Nadeshiko into the mix, along with Aoi's little sister Akari. The sisters try to play with Nadeshiko's head by introducing a smaller Aoi, then a blonde Rin, fully equipped with hair-bun. Does this confuse Nadeshiko? You tell me!
But the third OVA was a radical jettisoning of the YuruCamp premise to strand the girls on a tropical island, a place where winter camping is verboten! Forced to parachute from a malfunctioning plane en route to Australia, Rin, Ena, Nadeshiko, Aoi, and Chiaki are to survive on a deserted isle. My question ... who had the ramen on their person when they had to leave backpacks behind to strap on the parachute? A lot of plot difficulties you have to give a blind eye. These girls search for the ever elusive banana and fish for the 'big one' to sated those growling bellies. But they get good at this, allow them to engage in a beach romp (again, they left their backpacks on the plane. Where did the girls find the beach wear?). Happy times until they realize that they must escape ... from an island just off the coast of Japan and on the major sea routes.
One other reason OVA's are created is they give the animators an opportunity to experiment with the technique. The second season promises more camping gigs in the spring and summer, so why not try a brighter color schema? Just for kicks. It could become necessary procedures as the series has to change format.
As I hope I will find when I take in Laid Back Camp, Season Two. And, if I don't see them, I might just have a 'fit.'