1. Black people's hair doesn't grow or isn't long
This myth is huge and even believed by a lot of black men and women themselves, but let's think about this: why would a black person need a barber or a hairstylist, or go for haircuts in general if their hair didn't grow? What are they doing in there? Just walking around in circles?!? Nope, black hair grows just like European hair, Asian hair, Hispanic hair...well, you get the point...on average about a half inch per month.
The reasons many believe it doesn't grow are two fold: number 1 is, a lot of women and men with natural hair find the upkeep of longer natural hair very difficult and time consuming, and for many it can be, so to cut down on this, they keep their hair short or wear it in shorter or protective styling (i.e. braids, weaves, wigs) and don't actually allow it to grow long. The second reason you don't tend to see the growth that exists is because of the curl pattern. Natural black hair tends to be very curly, coily, and kinky. Think of people with straight hair as having jump rope hair. The rope when laid to the ground pulled end to end, is relatively straight with no bends. Black hair is more like a slinky. You lay it down, and it is coiled up tight, however, if you pull out that slinky from end to end, what looked on first inspection to have been 6 inches, suddenly turns to 2 ft. Black people refer to this as shrinkage which can be seen in examples in the photos above.
This is what chemical relaxers and heat straightening do to black hair. They relax the curls and straighten them out so you can actually see the length. Unfortunately, these processes can be very damaging to hair, so in order to maintain health and strength, a lot of people would much rather cut the hair then damage it in order to have their actual hair length visible.
2. You can't "do" anything with it
Say what? Black hair is some of the most versatile hair on the planet that can be styled in a million different ways, and that's before you even add a drop of chemical into it. The problem with this myth is that a lot of black women and men face hairstylists who consider their hair unworkable. All they can think is to attempt to comb it out into an Afro or cut it. It can be very frustrating because there is so much that can be done to it, and yet in the hair industry, you have a lot of Beauty schools and stylists who willfully do not teach or learn how to style black hair, and yet, these are potential paying clients like everyone else. These same stylists will do European hair, Asian, or Hispanic hair, but will refuse to learn and/or specifically do black hair. It is part of the racism that is routinely felt within the hair industry directed towards black men and women.
3. Black hair is automatically wild and dirty
In many a dress code across this nation, and the world at large, repeatedly, above any other race, black hair is continually targeted and labeled as being wild, unkempt, unnatural, and in need of control...or else. That or else means, a child or person can be kicked out of school, work, or told that they need to chemically damage their hair in order to give it a European appearance.
Natural black hair is NOT straight hair and never will be. In it's longer state, it cannot be brushed down and smoothed out nor is it meant to be, and to do so could permanently damage the hair especially with the aid of chemicals. Black hair is naturally curly and it grows out of the head in a curly way. It doesn't grow straight down, so another raced individual with the same length of long hair may be cascading down his/her shoulders as compared to the African American employee who's hair may be sitting up higher on the head. If an employer or school does not equally require person A to cut their hair, why do those policies only seem to pertain to those with natural curly kinky hair?
To be told your hair is somehow wrong or needs fixing or you're unfit for an education or to work somewhere is both offensive and racist, and shows a severe lack of knowledge on the part of a lot of individuals. Of course, every place should require that hair be on display in a neat manner, and you'd be hard pressed to find people who disagree with that no matter the race, but when those dress codes take neat to mean, hair can ONLY be straight which then = neat, or they specifically only describe natural hairstyles as "EXTREME!" they are purposefully creating exclusionary and discriminatory policies
Also, just because a person has dreadlocks, in particular, does not mean they never wash their hair. You can find people with dirty nasty hair in any race, but a particular style should not automatically mean this is a person who doesn't take care of their hair or themselves. Dreads, like any other hair that anyone else might have on their head that grows naturally, can be washed, and most people with dreadlocks and natural styles do wash their hair frequently. Seriously, you have to explain this to some people.