I've been fortunate to have had the opportunity to ride under the tutelage of some pretty amazing riders, ranging from Steffen Peters to Ulf Moller. At these world class training facilities, I was surrounded by a multitude of other riders and trainers all striving to be the best in the world. We all know everyone has a different personality, but I feel there are 2 types of people who make it to the top of the dressage world, and they couldn't be more different.
Type 1 - The Mathematician
This is what I would consider your classic Type A personality. Overly well organised, structured, and dare I say a tad OCD. They are the ones that bring a shelving unit to organise their locker at the barn and clean their tack after every ride. I call them the mathematicians because I feel their minds work in a 1+1=2 kinda way. They approach their training in the same way. Structure and discipline rule the world of the Mathematician rider.
Type 2 - The Artist
You know that girl who shows up to the barn with so much trash in her car water bottles roll out every time she opens a door? She's the artist. Probably running late, she approaches training in a creative way, often with rules the seemingly contradict one another. Flexible and non-linear, the artist eyes her canvas, the horse, as a giant puzzle and can work on little pieces here and little pieces there. But in the end, the puzzle forms a picture with all the pieces fitting perfectly together.
I have seen both types of riders excel at the sport of Dressage. I don't feel one is particularly better than the other, in fact, I feel their different approaches are equally successful. I once worked for a trainer who only started her day when inspiration hit her, sometimes not beginning her day until 4:00 pm and riding well into the wee mornings of the next day. I've also worked with a trainer who hand wipes his tires to his vehicle every time he drives into town. Both are successful Grand Prix riders and trainers.
What I do think is important is trying to figure out which type of trainer best suits you. Meshing with your trainer in terms of personality types is of the utmost importance, but always remember there is something to learn from everyone who has ridden down the centerline at an international level!