You could either keep making excuses, or listen to the people that are telling you about things that look odd. Yeah I guess because you used marker to draw that's understandable (then again, you could also chose a different tool, or draw larger to allow different thicknesses).
What I'm talking about is trying to make a story as to why the leg is the way it is. The eye does not lie, and especially in other people's eyes, will it be more noticeable that something is wrong. If you can't see them yourself, use a mirror and hold your drawing up in it as you draw it. This is eye training and lets you see mistakes.
The legs look wrong because basic perspective rules were either neglected or not known.
The arms simply just look like you forgot to pay attention when you drew them, and thus caused it to get thicker than the other one.
Arms and legs can be tricky, and you have to keep in mind the basic perspective rule when making them or they will never look right. Away from camera, smaller things get, towards camera, larger things get. The more its pointed directly towards or away from camera, the greater the ratio gets of small-large from one end to the other. Ignore this rule, and things will not look right.
So please, take the advice and try not to make excuses. I don't blame you, but I know my eyes and other people's do not lie. Its much easier for others to see your mistakes, and the important part is if you are willing to listen and accept the fact that it is possible they may be correct. Normally I would not have been this in-depth, but you seem to need it because you are denying the mistakes clearly visible by other people.
Good luck and I hope you take this into consideration. I'm not trying to say you suck or anything, just trying to help. We all have trouble as artists, and I myself am still guilty of many mistakes, but I try my best not to make excuses when those mistakes are confronted.
Oh, and also, judging by your recent post with the usual "scenario" of what happens when you post an anthro here, it seems to me that if it really is that bad, then maybe its just people in general that sucks, which I myself hate, because most of them will never learn or appreciate anything that is not within their realm of enjoyment.
