First off I bought the game for PvP only, and from the start considered PvE as a free addon, a bonus when compared to other PvP games.
Now there was a lot of talk about why Battleborn failed, why no one is playing it, what could be done to improve it, and I myself agreed with some of them, and added my own. There is no question that marketing wasnt good enough, that there are huge frame drops issues, that there is no proper tutorial introducing people to different effects and mechanics, and so on. However the drop in the amount of players was so big, that even with all those issues I still couldnt belive it. There was no such case before.
Recently however, based on forum observations, I started to think that the main reason for that could be PvE. What I never considered before was, what if people who quit were mainly PvE players who got bored with it, and couldnt find themselves in PvP. Because what I noticed is that a huge amount of people came here straight from Borderlands. However this is not a Borderlands game. Some of you probably played missions hundred of times, but lets face it, they are boring, nothing to compare to Borderlands. Not only there is less of everything, there also is no continuity of character development in terms of leveling, skills and gear, which is actualy what usualy keeps people playing. Hence people who often liked Borderlands and expected similarly rich PvE experience, would play few missions and quit when bored. Those people would often try PvP, but for a PvE player, often without moba or competitive fpp background, it would be hard to get into. This would explain the huge initial drop of players that happened. You see, PvP players like me tend to check what exactly they are buying, especialy when there are many games to choose from. So a PvP player who buys Battleborn, he should already know that this is largly a moba game, he should know about existance of leveling, skills, and gear, possibly even existing technical problems. And such player would play a bit to learn and see if he likes the game, as did I, because I only started to like it after finding suitable character and playing incursion for 3 or 5 times with it.
There is a lot of people on forums that would like additional PvE content or more lore, both things that PvP players usualy dont care about. In comparision hardly anyone requests PvP maps, and lets say it, for a PvP player the initial 6 maps were a joke, a reason why not to buy such a pricy game, and 9 is not much better.
The game tried to give both PvP and PvE experiences, tying them together by loot. I even liked that idea when I first heard about it, but for it to work it has to give a fully fledged PvP experience, and non repetitive PvE. I honestly think that if the game was released as a PvP only, and then we got PvE missions on monthly basis, it could had better chance to create a community that would got what it expected and would stay with the game. It wont work the other way around, because PvE in Battleborn is too limited for majority of PvE players, while PvP wouldnt keep them playing, and that is exactly what I think happened.