While the statement doesn’t need definition, i’m going to provide a little expansion…
The ego drives us to progress, and often fuels triumphs over ourselves.
The “No Ego” painted above the door refers to the malformed, over-inflated version that causes some people to think exhibiting some proficiency in one specific area somehow makes them a better person in all others.
The ego absent in our training room is that shown in an inflated sense of self, manifested in outward attitude towards others, and often driven home via apparel with ego-maniacal, nerdy, and usually amateurish sayings.
That sort, oft seen in a hard to conceal sense of snobbery, can usually only be held to test in the most limited of capacities.
It is quite true that the ones with the most to offer usually talk the least about it.
Keep the ego in check, only indulging it enough to stay progressive and as fuel to never quit when the skies turn dark.