Can a management consultant work like a doctor works?

this may sound strange, but I had this tought recently. As you know, we visit doctors, they diagnose us and advice us how to get cured and in sometimes, the doc does the job. It may take hardly 20-30 minutes

This is similar to what a management consultant does. You will say that, management consulting requires high amount of time, analysis and effort to conclude to a suggestion, and yes this is true.

But consider some fields, let's say online marketing. A person or a firm may want to know a quick opinion of a higly experienced consultant in this area, questions like which one of this concepts should I choose to have a bigger impact to this.

There are several examples like these of course.

My question is, can this work or are there some crucial points I didn't concider? I am not aware or heard anything like this, please point me to some if you know.

Thank you for your time.

There are people who can make a living doing the kind of consulting you describe (see e.g. http://www.nngroup.com/consulting/usability-evaluations/ ).

But I have to pour a bucket of cold water on the idea that you can become one of such people.

First, it only applies in rarest of occasions. There aren't many cases when someone is willing to pay thousands of dollars for a few hours of work resulting in a little bit of wisdom. For example, that wouldn't work for programming jobs where you have to deliver code.

Second, it's a massive marketing problem. You have to convince your potential customers that your service is worth it. For example the NN group can charge those prices because the principals are thought leaders in the field of usability, wrote influential books on the subject and have been doing usability for 20+ years. Chances of becoming such recognized thought leader in your field are practically zero - people who can pull it off are extremely rare.

It's a nice job if you can get it, but you probably can't.

It can, and probably even better than a doctor. To be a doctor you have to study for many years, train, get licensed, and have continued education all the time. To be a "management consultant" you just need a business card that says "XYZ, Management Consultant".

Whether the clients will actually come is an entirely different issue. While it takes the doctor 20 minutes to diagnose a flu, it also takes some of his vast knowledge and experience, and pattern matching to one of the most commonly spread viruses. Cancers are not diagnosed within 20 minutes. The question is what kinds of problems you want to consult about - trivial and simple, or serious and complicated?