Barrier:
Over Enthusiasm....Is It Good For Any Organization!

I have actually said this. But, in my defense, it was after years of having this said to me and I was honestly just trying to protect/warn a new employee from getting his heart crushed like I did...

Been there.(Have been)done that.
I agree with Jan it is a Management 1.0 skill (bug in that case) from over polished shiny and smooth pseudo-leaders;
Beyond this first level analysis, enthusiasm must be encouraged while it must be deciphered through the cultural prism big time.
So it is easy to calibrate into an homogeneous population sharing the same benchmark modulo the personality dispersion.
it requires some additional tuning when joining a global mixed group. Room filling is definetely a function of personal space protection factor, not only physically but acoustic wise. Compare urban indian traffic jam and "OK Honk" codes with a Japanese metropolex transportation.Likewise Thai jam is also misunderstood and a different animal.More like a quiet elephant that many pre-suppose.
Enthusiasm is never to be hidden nor to be tuned down, only it must adapt to the peers/customers/bosses captors sensitivity, in order to remain efficient and contagious.

Interesting. I see this all the time. People from formal companies and mostly older, tend to correct this kind of behaviour and telling people to "be professional" or "these people are used to meet excecutives, so behave".

I think much of this is a Management 1.0 / 2.0 barrier - but first and foremost, uncertainty from the C-suite / management about the change in the way people communicate today. We are less formal than we used to be and excited people are more common. The language of the social feeds move into everyday worklife and people not used to this new way of communicating - nor used to enthusiasts, can react negatively. I also removes some of the traditional hierachies, where the boss was the wisest.

But, the enthusiasts need to be aware that in the heat of the moment, patterns of interruption and over-excitment can emerge and a person can really fill up a room too much.

I hope this will change over time, and that we can loosen the ties a little and bring more of our personality to work in the future. I like original people with enthusiasm, I really like them. I trust them easier. I am tired of the carbon-copy suites that has been around to long, trained to tell sweet little lies to us all :-)