I don't think there is anything wrong with trying to help someone or analysing their movements/skills, but I think that sometimes the TONE people use in helping others is what defines it as either being helpful, or then coming across as crass &/or rude.
The underlying tone through which you communicate is very important in your daily dealings with people. You can help someone, & remain humble, or you can resort to criticising them & then coming across as a douche-kanoo.
In our class, students will ask me to point out to them whenever I feel like they are doing something wrong, so that they can then improve on whatever it is that they are struggling with. I analyse their movements via the instructions of our teacher though, not based on my own knowledge (I don't have enough knowedge or skills to do that, lol), i.e. Let's say they stand in Ichimonji, & their heels aren't lined up, or perhaps their 45 degree angles are a bit off; I will then just point that out to them & the next time they do it, or after that, they will actually do it right, after which I will praise them for doing so. It's all about your attitude towards people.
And if you carefully observe people's behaviour; they will not have a problem with you trying to help them if you come from a place of understanding & lowliness. If you tell them "Don't worry, I struggled with "xyz" technique as well when I was at your level, it takes time"; or "I'm also still struggling with "xyz" technique"; they can then RELATE to you as a human being & not feel bad or insecure for finding something difficult.
However, if you're coming from a place of superiority, someone who has little patience, someone who is critical, & someone who humiliates the mistakes or lack of skills of others, then people will definitely shy away from your "help".
It's all about vulnerability. If you cannot be vulnerable with people, they will always see you as a superior being & not be able to ask for your help, hence they will feel inferior to you. On the other hand, if you are honest & raw with them (bring your guard down & swallow your pride), they can relate to you & that then establishes a foundation for connection.
Perhaps I'm coming from a place of too much estrogen to some on this thread?
. I don't know, but it really does help, I've found at least. There could be millions of other options or scenarios to apply to a situation like this that I'm not aware of. So if someone disagrees, or has something to add, please do.