There are plenty of people that have good ideas, as well as plenty of people that seem to comprehend those ideas, but, in fact, they often don't have both of those things working in synergy. It simply isn't good enough to have an idea, if you are not willing to take that idea and fully envision it, by actually doing the constructive things that are necessitated by that idea, rather than moving on to the next idea, and then the next idea, and so on.
When you have a really good idea, you should actually right then and there, begin to sketch it out into a broad outline and then, have the persistence to subsequently take that outline and to thereby properly study and to define it. If you don't do those things, you will not really know how good that idea really is, for without having investigated it further, your idea simply doesn't have enough background or traction behind it, and if you fail to stay on top of that idea, it will soon, like many a good idea, just sort of fade away.
The thing is, for an idea to actually be worked into something of substance, not only will it probably require the valued input of other people, it is also going to have to be viewed from every conceivable angle, both positive and negative, of which that learning process, will probably in and of itself, determine whether that idea has enough merit to really consider it further. In order for that to occur though, you have to concentrate fully on just that one idea, and can't allow your idea to get crowded out by all the other things that can and will divert you from the proper attention that you need to provide for that one idea.
It isn't so much that our minds are so simple, that we can only take in one idea at a time, for that isn't it, instead it has everything to do with recognizing that ideas in this present day and age, necessitate a very vigorous examination, and further that this idea is provided the opportunity and the space to clearly meld into the mind, so as to be as completely comprehended, before testing it in action.
Those that have good ideas that come into their mind, must understand, that without actual specifics, and without a diligent and dedicated study of that idea, that the idea, no matter how beautiful it may have appeared to them at first sight, simply has not been studied long enough, with persistence, and with focused concentration, for it to be really known that this idea, actually has true value.
If that idea is not able to capture the mind, fully, then perhaps it wasn't such a great idea to begin with, or perhaps the fault lies in the inability to get that mind fully around that idea and to study it in a way that does that idea, justice. The idea needs to be known in a manner in which, it has been studied from multiple angles, investigated, researched, and been vetted, then, active steps must be taken to make that idea happen, for if that is not done, then the idea will probably just vanish.