...without having the large picture described, i.e. without the OP supplying a lot of (possibly irrelevant) descriptions about what the product is expected to be used for, and why it needs a specific feature.

I have on a number of occasion been helping people fighting through all the hassles of getting a concept to work. And suddenly, days or weeks after the first post, the OP adds a tiny little piece of extra information, and suddenly it has been apparent (to most people but the OP) that he/she is fighting with a problem that shouldn't have been solved in the first place.

Think about how hard it is to try to tell someone, with just words - no illustration - how to tie the shoelaces. And then, the OP suddenly mentions that his shoes have zipppers. Sometimes it's a tiny little detail. But sometimes it takes a huge amount of information about a problem just to let the helpers see the important picture and be able to suggest a good solution. And a good solution may actually solve a completely different problem.

You can fight trying to convert a frequency to a voltage and then use an ADC (with proper voltage reference) to measure the signal value to allow the original frequency to be computed. Or you can measure the frequency by just measuring the time for n periods of the input signal. With too little information, a lot of time can be spent trying to help with getting a good voltage reference without knowing that the real problem is getting the f to V converter to be linear. And no one will know that it may be possible to throw out both f to V converter and ADC from the equation.

No flowchart will ever be able to catch all possible questions to ask to get a complete decision tree. And with a too complex flowchart, most people will get confused and ignore the flowchart. If they even did look for it in the first place.