In my opinion, I will say all are important to the success of a project, we need a developer to have a project,we also need a good team to have an outstanding project and the project also need to be accepted by the community to have resounding success.
The thing with the three category mentioned by the OP is that they are all very important to the way the project eventually turns out. On a normal day, if there is nothing catchy about a project, then there is no way you will even be able to get the attraction of the investors into your project, which makes the possibility of having a community not to even be a thing.
What is important is a good, experienced and hardworking team that will be ready to build a pretty good product, and this is what the community will be centered on. You cannot leave the main thing, and focus on another, when it is that main thing that will bring about the community in the first place. For the success of the project eventually, everything is equally important.
Normally, how will a tree be able to have some fruit without its branches? That is the way everything is intertwined. Firstly, the team comes first, which is why I see the whole team as developers and innovators behind the project, so in most cases, to be able to build a solid community, there should at least be some good team and developers working pretty well to at least keep enticing more investors into their product idea. Now, as the support keep growing, so will the community keep growing, and what is the success of a project without its community support ?