>Some seniors just respond with "rtfm" or "Yeah I got to figure that myself too, won't hurt if you try that too..." to every single question.

This is lousy behavior not only from a senior, but from anyone. If someone on the team spoke like that, I'd pull them aside. Granted, if the frustration had grounds because the other person wasn't pulling their weight, I'd pull that person aside, too.

One of the things I test for in interviews is behavior towards vulnerability. In the early days, I would meet the candidate not necessarily communicating on my role. I would then ask a silly question as if I did not know the answer and observe the reaction of the candidate. Some take the opportunity to explain to me how things work. Others bounce on that opportunity to do two things:

- Give me bullshit: they imagine I am not technical if I'm asking this question, so they think they can get away with it.

- Shift towards a condescending tone: it is amazing how you can see that shift as in "Oh... you don't know this". Some become discourteous: "Do I have to explain this to you?", roll their eyes.

Another test is, in a technical capacity, say something you know is wrong. How the person will handle this situation? How do they debate? Will they be insufferable when they think they're right? (you want to hire people who are right more often than they're wrong, but not necessarily be douchebags about it as the goal is to solve the problem, not to prove others wrong and do a victory lap on every small matter). Will they just agree with you? Do they aree with you because they didn't know you were wrong, or because they knew and preferred to let it go (which you can't afford because you want people to check your thinking and tell you when you're wrong)?

Another test is say something you know for a fact is right, but say it with a lot of self doubt. Do they make their decisions based on what they perceived your degree of confidence is, or based on facts? You don't want people to debate technical matters and "go for the kill" because you don't seem sure. You want people who'll take that pertinent remark said with doubt, and actually do some thinking about it. Those who don't tend to have a cargo cult mentality and arguments of authority work too well on them.

These behaviors disqualify candidates for several reasons:

- Unless you're doing something trivial, you're pushing your comfort zone and are in the "ignorance zone" while trying to figure out solutions to a problem. We spend a lot of time in this zone, which means we ask each other a lot of questions, sometimes basic questions to check we're going at it from the same hypotheses. A person like the above would become intolerable in this situation as it is clear they have this attitude mostly because they haven't worked on problems non-trivial enough to become humble, ask questions, and risk being silly systematically to get to the bottom of things.

- We must be able to explain things for people with different sets of skills. For example, when a team has several people with different skillsets, each one person should be able to safely ask questions to another person with skills they don't possess.

- That disdain for "non technical" people does no good. From what I have seen, it tends to be a sign of low general intelligence. Talking down to someone smart because they can't code is plain dumb.

>Some very sharp technical minds might not be very good in interpersonal areas. So don't feel bad if you look stupid or someone is a bit nasty.

In my experience, sharp minds tend to value effort and interest of the person they're explaining things to. It is an investment and they're more than willing to explain things to someone again when the person shows they took what was said last time, thought about it, researched things more, came back with more subtle questions that show a deeper understanding than they had before because they're struggling with more nuanced problems.

We often write emails to everyone on the team, going through the rationale of things, point by point. The expectation is to receive a "pull request on our thinking" to fix a bug or add a feature. These are extremely valuable because time and time again, one or more persons on the team would say: I thought we were doing X because of Y, but it appears it's because of Z.

Of course, this gets easier when you have a way of work with colleagues who, when you solve a problem, will stop you and say: "How did you go through it?", "How did you know you had to look at that process?", "How did you know it was time to make that decision?". We tend to talk about everything: product, business, marketing, ecosystem, the whys and hows, and "junior" people are there so they learn the process behind this. They learn what is a priority and what is not and why it is that way, so when something changes, they can update and make decisions on their own to optimize for what we're going for.

As you said, anyone ought to be adding leverage. People tend to think you can't do that in an individual contributor role, but you can. Drafting good issue templates to lower the barrier to writing good issues that are easily parsed adds leverage. Taking meeting notes and sending them to everyone so people can have a written record to track progress, or spot discrepancy between what was said and what was understood and correct it upstream before people work on the wrong thing adds leverage. Factoring out what is "taught" or "told" to newly hired people and putting it into an onboarding document that can be improved by everyone adds leverage. These are all things that can free up considerable time and reduce the frequency of "the senior having to do something".