Hair comes in different shapes (straight, wavy, curly) and sizes (diameter of the hair strand- fine, medium, coarse). These combine on a head to produce a head of hair. Every head of hair is unique to each person and has its various ways of needing to be cared for. Every type has its pros and cons, its ups and downs, its good and bad hair days.
Hair shapes (straight, wavy, curly) each have their own demands. Straight cannot seem to hold a curl. Curly has a hard time being straight. And wavy can go either way rather easily it seems. Straight hair appears consistent and uniform. You always know what you will get...straight hair. Wavy likes to have a tight wave one day, but looser another day depending on the season of the year and what the weather is doing. Curly hair does its own thing and sometimes in a big way when there is humidity present in the air. Moisture is a must for the curls. In the end, I do not look at hair shapes as one being better than the other. They all have different requirements. They are all their own works of art/shape.
Hair sizes, as in the diameter size of the hair strand, also call for diverse hair-care routines. Fine is the smallest size, medium is...well...medium-sized, and coarse has the biggest diameter size. Fine hair can be fragile and lanky. Medium is...well...medium. Coarse can take a long time to dry and tends to be bulky feeling (depending on the density of hair). A positive for fine hair is that it dries quickly. Medium is not too big and not too small, so it is an average of the best and worst of fine and coarse, and it is...well...medium. Coarse hair is very strong and can take on much chemical change (color, straighteners, perms) and heat before it begins to look ragged because of its dense amount of cuticle. The diameter size of hair does dictate some things, but it does not have to define you or your style.
Ultimately, the best remedy for any head of hair is to know your hair. As Philip Kingsley states in The Hair Bible, "The only way to correctly choose [well for your hair type] is to know your hair and be able to describe it...."