Because most people are lazy. There I said it.

It is far easier to let your government step in and make you do it, or more importantly make someone else do it for you.

Face it, outside of the truly poor, people will spend money on non essentials all the while some essentials go unpaid. I know professionals who do not put money away for retirement, do not go to the dentist, do not go to the doctor, do not, do not, do not. Get the idea? I love the complain of many, they don't have the time or money. Seems to me most have the money but their priorities are to smart phones, expensive cable plans, cars, or other frivolous expenses.

So why should we expect people to pool their resources when they cannot effectively use what they have? The world needs visionaries, fortunately every once in a while one comes along who has the wherewithal to act on his dreams.

You're question isn't quite clear to me. I think I have an answer, but what exactly are you asking?

Not to completely disagree with your sentiment, but I think there is a large difference between having the resources to execute your own vision as opposed to having to partner with a large group of people and find a common vision. Especially when you start getting down to details. Grand plans are a lot less alluring when you don't get to be the boss. Not that we should let that be an excuse. :)

Everyone wants to be a chief, not an indian. They don't want to be contributor #1987123 to a big collective effort.

If they can't be the visionary genius, they would prefer not to play.

Arguably they are, but they are delegating all the management. When you invest your money or even put it in a bank, you are pooling your resources with others to accomplish things. If you pay taxes, you're doing the same thing.

Your question is better phrased as: why aren't we forming more organizations to which we directly contribute our time and talents, where we have an intrinsic stake in the outcome?

And I think that's pretty easy to answer, it's all the same reasons startups are hard plus a few more. It's hard to convince others, negotiate internal politics, and set up all the logistics. You also have another problem - if people are not rewarded with money, they tend to do only the things they find intrinsically satisfying.

The kinds of people who are willing to solve the above problems are called entrepreneurs, or politicians, or community organizers, or sometimes artists. However, there may be some technical hacks that would help. Kickstarter helps solve some of the questions above, particularly about where to put one's resources.

I think some of the other answers to your question are unnecessarily pessimistic. If I can take some of them one by one:

"People are lazy": not actually true. People are willing to work crazy stupid hours for the status items mentioned, like smartphones. Often they are doing this for social status. This suggests that people aren't lazy; they're irrational, and bad at managing their resources in a way that benefits them optimally. That is actually a useful characteristic if you want people to commit to something with a small rational chance of success.

"Everyone wants to be a chief": We want lots of things. The ideal is to be personally recognized within the solidarity of a group. A clever leader can rewire your motivations so that to obtain personal fulfillment, you start doing group-beneficial things.

Isn't this what kickstarter accomplishes or could?