Your hair is a part of your genetics so that does mean that not everyone can get curly hair but you will never know if curls are in your genetics if you don't understand what your hair needs to be curly in the first place. Most people don't just wake up to super curly hair and because they can't add some cold water, Cantu curl cream and see amazing curls they assume curls aren't in the cards for them. That couldn't be further from the truth. But you wanna see if you can get curls to answer these questions.
Have you ever had waves?
If the answer is "yes", then it is 99.9% likely that you can get curly hair. Yes, waves are just laid down curls but it takes a completely different thought process to expose the curls standing up versus stretching them out and lay them down. As a matter of a fact, by looking at the size of your waves you can tell how big your curls will be.
The difference is that you can have decent waves and have dry hair, damaged hair and unhealthy hair but if you for one second think you do that with curls, you are sadly mistaken.
Do you have shrinkage?
If you naturally have shrinkage then there is a high probability that you can have curls. The harsh part about this is you actually need shrinkage to have a nice shapely curl. Think about it a curl is what? Almost spring-,or coil-like. If you were to stretch this out to make it as long as possible it would be impossible for it to curl. So stop fighting your shrinkage, if your mission is curly hair.
The caveat to all of this however is understanding that everyone has different genetics and those genetics mean that we all can have curls of different sizes, shapes and sometimes even different methods to get those curls.