Not long ago, if you were to ask me if I found my salary comfortable, I'd probably tell you no. But that's because I was ridiculous with my money. For example, my entire extra expenses one month, meaning stuff that I bought that I in absolutely no way needed, worked out to about the same amount I owed on my credit card. Not smart. Calculating that was an eye opener.
Juvenile mindset, that's all. "I need more money to spend" rather than "I need to spend less money"
Like people said, it's all dependent on lifestyle and state of mind. I could be comfortable on 30k, and I have been.