Once ideas have been collected (usually by brainstorming), they need to be evaluated.
It is important to determine
exactly how the evaluation is to be done. It is better to have a small, multi-disciplinary team doing it, on the basis of two heads are better than one, but not too many two or three people would normally be sufficien to provide diverse enough viewpoints to ensure that personal bias does not lead. Also, members with the skills to estimate costs and requirements for implementation would be needed.
There are rather mechanical techniques for this, wher the "best" ideas are selected, criteria determined and the ideas evaluated against the criteria. However this does tend to defeat the purpose of brainstorming, as personal bias may determine which are the best ideas!
A method which requires more work but can yield excellent results is to evaluate each idea as to what it will accomplish' what are the befits from the idea? What is there to like?
It is often found that a seemingly "wild " idea has an appeal because it encapsulates a fundamental requirement, although its implementation as stated may be impractical. Try to determine why the idea is so attractive. Then see if this can be achieved in a more practical way. such ideas may get to the heart of the issue which is being addressed.
Then again, several ideas may be combined to achieve a better end result. Although separately they might achieve only incremental improvements in the situation, in toto they might well have a significant effect.
At this stage, those ideas with the fewest or least significant benefits may be dropped, although there might be a few where implementation would be relatively cheap and painless and which do offer benefits and these might be considered for implementation on their own merits
Implementation of the ideas should be considered What are the resources, effort and costs involved? How practical, in these terms are the ideas?
One may not end up with one proposal only only, but with a basket of interrelated solutions which contribute to the solution.
It would the be necessary to make recommendations and to decide as to which should be implemented.
