The hard job of growing great Scrum Masters - 2

As you might guess, I'm really interested in this subject for taking the time to write a second post about it.

Few weeks ago I was talking with one of the Product Owners in my team (I am currently coaching the PO team). I had asked him to give me feedback on my work and we happened to talk about what I think is one of the missions of an Agile coach: to recognize Agile talents.

Surprisingly enough for me, he could recognize this as a very valuable point, but the rationale behind his belief challenged my current thinking quite a bit.

We came to discuss about what he considered as key characteristics for a potential Scum Master.

"There are some key qualities" - he said - "that a person who wants to be a Scrum Master must have and cannot be learned, regardless how many books you read or how good your coach is!”.

I must say this was a bit hurting my self-esteem: I thought I could teach or help any apprentice Scrum Master to learn practically any skill necessary for the job.
At least until then, when I realized he had a valid point.

But then I asked myself: what are these skills or qualities which are essential to hire a new apprentice Scrum master?

This question reminded me a blog post from Esther Derby I had read some days before, called Scrum Masters and Agile Coaches: More than a Title.

With the usual inspiring style, she talks about what are the Essential Qualities for a Scrum Master (Initiative, flexibility, optimism, determination, resilience, working in a team environment, supportive, not cowed by authority) and what are the Desirable Qualities (Detachment, discernment, Able to navigate conflicts).

However what hits me most is what she calls The Elimination Factors, patterns of thought and behavior that would eliminate a candidate from consideration. 

Here they are: Preference for directing others, defensiveness, judgmental attitude, low threshold for frustration.

The most interesting and surprising coincidence for me was that 2 of these relate exactly to the key qualities my colleague Product Owner mentioned and was able to see given his experience in Scrum: impressive, isn't it?

But what is your view about this issue?