Bitter consultant

So I am now PADI open water certified -- I am now allowed to dive to a depth of 18M. You may wonder why I'm not screaming for joy. Afterall, this was one of my goals while in Thailand and I accomplished it within 2 weeks of being here. Well, the truth is, the course was a bit of a let down. I thought that by the end of the course, I would feel completely at ease being deep in water. But I am not. I thought the calss would be loads of fun. But it was not. Why? It's all my instructor's fault. Guillaume.
One would expect a diving instructor to be cool and carefree - just totally chill but passionate about diving and enthusiastic about encouraging others to dive. Unfortunately, he was nothing like that. He was friendly enough, but had no patience for his students. He did not take us step by step through the prcoess. Whenever we made a mistake, he would say "use your brain!" instead of explaining to us what we did wrong. ANd instead of making sure that we understood everything clearly and can do them properly, he jumpd into a new topic or technique the moment we accomplish the task once. Tell me, is that the way teaching is supposed to be?
So you might wonder why he is this way. I found out during dinner after the final dives.
1. He's French
2. Worse, he's a Parisian - no freaken sense of humor
3. Grew up in Detroit - sucks for him
4. He is a bitter ex-Accenture consultant with a MBA. And yes, he is now a diving instructor.
That's right. It all makes sense now. He's just like all the other crappy, cocky, stuck-up consultants I've ever worked with. While bold enough to change his lifestyle and do something he cares about, he shed non of the negative consultant traits doing that. When he found out that I too was a consultant, he talked non-stop about how much it sucked and why he's in Ko Tao diving, etc. etc. He's been there for about 1.5-2 years and still so bitter. It's sad.
So why did I go on a rampage about Guillaume? Out of fear that I am like him. That I too am bitter. I just hope that I am not as mean or unapproachable. If I am, please let me know. I do not wish to be a bitter person.