Irish Goodbye at Work

Irish Goodbye: When you leave any social environment without telling anyone.

In Korean Culture, I need stand up and vow to everyone passing me especially who has higher job level than me. The level usually determined by age. I left Korea when I was 30 yrs old (relatively young age) with 10 yrs of professional career in there, I am very good at expressing greetings and partings to colleagues at work. I became an Irish in terms of salute years later.

Fox

Recently, few of my team members complained why I don’t say hi or bye when I come and leave the office in San Francisco CA USA. I am not ignoring you guys.
Like most of Silicon Valley companies, there’s no specific work hour at my current job. Few people comes as early as 8am. Some are coming around lunch. I’m almost always getting home at 6pm. Others usually have dinner in the office around 8pm. Really no pattern of commute. I'm surrounded by about 50 ppl from the sight of my seat in an open floor plan (A typical startup office layout). It will be horrible to repeat "Good morning", "Good afternoon", or "Good evening" to all. Here's why:
Software engineering is a creative and brain intensive job. To do the job, you need to be concentrated. Psychologists calls it “FLOW” state which is the mental state of operation in which a person performing an activity is fully immersed in a feeling of energized focus, full involvement, and enjoyment in the process of the activity. It usually takes 2-30 mins to get there for me. When you’re in “FLOW” state, you’ll be very sensitive to noise and various obstacles. It takes another 2-30 mins once it’s broken.
Not notifying that I'm coming and leaving is not to break their "FLOW" state. I'd say becoming Irish is a way to protect knowledge workers from the distractions.
You'll find myself as a polite Korean out of office ;)