It could be one of a few things!
Firstly it may be mare thinking, you know what, I prefer counter canter and there ain't no person going to get me to take the right lead ;)
Secondly, stiffness or pain. Remember its winter time now, its cooling down and if she's got any aches or pains it may be easier for her to do a counter canter rather than take a correct lead, which may be why she wouldn't do a flying change too.
Thirdly, it could very well been how you or your instructor rode her. If her nose wasn't on the left hand bend, and either directly ahead or slightly to the outside, she'll pick up outside. My suggestion would be ensure she is fully warmed up, loads of circles etc, then do a 10m circle, make sure she's bent to the left in a trot, then as you finish that, ask for canter, as she'll already have her nose turned in. Use loads of inside leg, over emphasise if you must! But give it a go. I'd make sure she's not in pain first, check her saddle, and that she has no knots in her neck, shoulder and back.
Hope this helps!
I don't think she is being a mare as she is the least mare like mare I have ever seen lol, Molly is a supper compliant horse! It is starting to cool down, but not terribly so yet. The last time I asked for her to canter on the left lead was at the very end of the lesson so we was well warmed up. I tried asking while going around a turn and lifting my inside hand and bumping with my outside leg. Normally I just have to give a bump with my outside leg. I don't think it's the saddle, I always ride her in my saddle, I've been riding her since January and checked the fit before the first time I rode her, and after every ride I inspect the sweat lines and they appear even with no dry spots. I'm going to the barn soon because my mare is getting her feet done(I board my mare there but ride Molly for lessons as I'm more confident on her since I fell off my mare) So I will lunge her and see how she lunges and see if I find any knots. Could a bad shoeing job cause this? The farrier they use is terrible, he did my barefoot mare once and she was tender footed for months, all their horses feet look so wonky, could the shoe be wrong on her left front causing her now to want to pick up that lead?
I would also suggest pain. My older guy started not wanting to take one lead as he developed arthritis in his hock. That would be what I would eliminate before anything else.
Maybe I will pick up some msm for her, it's about all I could afford for someones horse other then my own. I ride her so much and really have a bond with her and feel like she's my own,I'd hate for her to be hurting.
It's very possible your weight in the saddle made it uncomfortable or difficult for the horse to pick up the correct lead .. as suggested before, it could very well be pain. Does she lunge on the ground to the left? See how she moves without a rider or ask your instructor to ride her.
My instructor did ride her with the same result, I'll lunge her today and post back.
When you say lesson horse, is it a true lesson horse as in riddent a few times a week only by folks taking lessons? If so there could be a number of issues. Could be an old injury, arthritis, stiffness, or even lack training. Lack of training might not be the right word because if it's a lesson horse it's probably trained well and possibly even a retired show horse. I mean, if it's a lesson horse then it probably knows what it can get away with and if cantering on that particular lead is harder then it's not going to do it. Not if it can get away with saying now!
I would try asking "the wrong way". I would pulling on the outside rein when asking for it. I would have his head turned slightly to the outside which will force him to throw that inside leg forward. It's not the proper way but it should get the lead...
She is a true lesson horse. She was a race horse(you would never know it tho!), then a polo pony, so she has been worked hard early in life. She used to prefer cantering on the left lead according to my instructor, but now she just won't.
I have a friend who had a difficult time getting the correct lead going clock wise. It was because her horse was unbalanced.
I had her sit up tall, open her chest and bend her mares ribs around her inside leg. While supporting with the outside rein, I had her dramatically open up her inside rein, with her palm facing upwards as though she was unlocking a door *you know how you twist your wrist when you do this?* Then I had her look to the inside turning her shoulders with her, ask for the transition and whamo - her mare would depart on the correct lead.
I'm not sure if i'm coordinated enough to do all that at once
But I will give it a try, I might ride her today, not for a lesson, but Val lets me ride her if she isn't using her for a lesson, sometimes I'm just not up for the challenge of riding my own horse lol. I'm going to lunge her today and see if I can get the correct lead on the lunge, if I can I'll ride her and see if I can get it today. I feel like it's become my mission to get her to pick up the left lead! Which is good for me because It gives me something to think about other then actually cantering!