Unfortunately with all the reputation Krav Maga originally got as the most effective from of self defense and hand-to-hand-fighting, in many cases you better off taking Zumba lessons...
Krav Maga Instructor should be a professional Instructor. As such while he will make a living out of teaching or even just teach out of a hobby or compassion to people in need, professionals strive to provide professional service. The nature of thing someone must exchange services or cash to receive training unless they are provided for free.
I remember there were always those that used to come to many Dojan and just sit and watch... Later they practiced at home and some of them at some point opened a martial art school...There are those that pick it up from Hollywood movies.
In a way Israeli Defense Force Krav Maga was similar in its spread to Judaism. It did not seek new souls. When it went civilian, it provided Martial Arts like Dojan places of retirement to some of the ex IDF Krav Maga Instructors. Eventually, they had students that opened their own Dojans.
The form of training the original Krav Maga Instructors received was very different however than the formal training received in the vast Dojan of the world. But they chose to continue the original Dojan tradition and provide traditional training using the old world.
To make a long story short, if we were hoping to really learn intensively Krav Maga in the original way it was designed, we need to stay away from unprofessional "actors!" Influenced by Hollywood and China Kung Fu film industry, any one that can keep up with a tough looks and circus acrobatics could eventually open a successful Dojo!
Most humans that come to the Dojo, expect to improve themselves in fighting skills, self appeal, self confidence, etc. They are usually being diverted into a continuous cycle of good behavior (demonstrated in hard training) and a reward! Well this model provided a living for many families over centuries, but not the best self defense service.
Not that these Dojan emphasized self defense as the key benefit, but when I think about the original Israel Defense Force Krav Maga, I naturally think about Intensive acquisition of self defense skills. So When Imi died, and the reputation of the Israeli Defense Force at large piggybacked the watered down civilian Krav Maga, other martial artists were forced to at least take a look at it. Most of them were too proud to pay new dues to anyone.
In addition, there must have been also those that were willing to pay, but also Civilian Krav Maga instructors that were afraid of competition. Well let's assume you train for 7 years in few tough full contact martial arts and already have thousands of students. Do you think it is easy to suddenly change your training system even if you are astonished by the potential of Krav Maga?
Well it looks like after many years many instructors chose to "steal"/Adopt the name Krav Maga on the grounds that it attracts more students! But in essence most of them are no different than the guy that used to come and watch free classes of a local dojo, or in the worst case scenario, the guy that was going to Bruce Lee's movies full of action, and opened a Dojo based on that. Remember Hollywood firm are made to impress. In self defense you do not have time to impress anyone.
Your only wish is to get out alive without too much trouble. So now we have at least 4th generation of so called Krav Maga Evolutionists mostly based on marketing and far off from self defense. People go to schools, learn nothing applicable to what they wanted to learn, but then they use their credentials to open a business and their prior consideration is to bring income. Things are tight especially at the beginning.
Everything is product/service oriented. Well history is something that can be falsified in the long run. But in the short run, it cannot if you take the time to research it well! For the average gullible citizen, superficial knowledge is not enough to make a smart decision.
The Major problem with Krav Maga is the approach to the content to push into a short curriculum. Misunderstanding the concept is the basic element for this problem. The original Israel Defense Force had a relatively short curriculum listing less than one hundred and fifty techniques that can be taught intensively in less than a week's time. In shorter courses there was tendency to extract techniques from the curriculum and serve them to the public.
The idea in running people through techniques it to give them some hands-on-experience of what to do and have them develop their navigation system understanding the human body capabilities.
However if your environment emphasizes a strict adherence to techniques without further explanation you are not acquiring good self-defense skills. In modern world under danger that justifies going for the kill, you better have an accurate and precise skills of all your opponent's options before they materialize.
Just going through several techniques might help but will not cut it. If you have no choice and give your student less than a complete picture of what to expect and how to go about it, the worst thing you can do as an instructor is shut up their thinking and curbing their curiosity.
Moreover, it is very important that you tell them to try and connect the dots and give them at least a good overview of all the essence of self-defense. If you are too broad about this, you are not deserved to be called a Krav Maga instructor!
The whole idea about Krav Maga is to train individuals to respond successfully to a chain of blows, kicks, throws, restraining, knife jabs, stick jabs and pistol/Assualt rifle threats and prevail.
This must be done by training them in execution in most efficient attacks the human body is capable of through sharing the accumulated experience in the world of hand-to-hand combat. So techniques teaching are basically walking students through a devised solution to a particular scenario.
Once students are having a hard time remembering or commanding their bodies to do it right, you need to take a step back and rehearse prior steps. When you reach the complete picture, students should be able to utilize most of the techniques learned knowing intuitively when to apply each one of them within a split of a second, using sound judgment.
In a way learning Pure Krav Maga can be compared to learning the navigational Coordinates of the globe, where the human body is the globe, and the student needs to learn the best way to overcome all kinds of terrain moving from one to another quickly using judgment in applying sound principles!
But first you need to find an inclusive source that helps you comprehend what you are about to vest your time in and how exactly it will fulfill your desired expectations.
Do not short yourself out of what you need. I recommend reading my book Krav Maga - Use of the Human Body as a Weapon. You can try reading the first chapter for free on amazon and see if you want to invest few dollars before you make any decision. You can also pay a one month membership equivalent and get the Pure Krav Maga - Self Defense Mastery Training videos to visualize it.
Understanding exactly what you are about to invest your time in is essential. You do not want to spend your time and find that you did not get what you wished for!