You should rephrase your title as it should be the importance of a good and supportive community. A project can have any community considering airdroppers, bounty hunters etc can also be considered as a community but not a supportive or productive one since this guys are only interested in the reward you give to then after a certain period of time then off they go. They're not interested in the long-term goals of the project, just the short term success which will be conducive for them to sell their reward for cash.
Having a community filled with just ICO investors doesn't gaurantee a strong community too. Most of those investors are just short term profit seekers hoping to profit from your project and move on. A strong community should consist of investor would believe in the idea the project is trying to sell, to the general public. A supportive & productive community is a very important factor in the success of any project and that shouldn't be overlooked.
These communities not being a productive one can still be understanding, because they are not part of the team and when it comes to project productivity, that should be the sole responsibility or interested of the developers of the project and the team, but for being supportive, I think investors has really failed in this regard.
You may be interested in the reward but how would the reward come if you are not being supportive, and how do you become supportive, being supportive is not only by putting money in the project to make it string, but one of the characteristic of a supportive community is that they will make sue the hype of the project does not end to when the campaign was launched, but it would continue even after the project has been launched and they will continue to promote the project in their own way like it's their life.
