The second and third sentences are reasonable; yes, we should all try to step out of our comfort zones every now and then. But I vehemently disagree with the first sentence. I have no scientific studies or similar sources to back up my views, but I've read several articles that very accurately describe the way I feel about this topic. For introverts (and I count myself here) social interaction is for the most part an energy drain, while for extroverts it's an energy source. There's people that cannot stand the idea of staying home on a Friday night and would actually feel down if they did. They crave social interaction, loud places, being around people even if they don't know them. And there's other people who cannot stand the idea of going to a club and party until [whatever time] in the morning. Loud places, crowded places, forced conversations, just suck away our energy, they don't make us "feel alive" or anything of that sort. So we stay home and read books, or attend small social gatherings with our close friends.
To summarize: in general, extroverts get energy from social interaction, and introverts lose energy in them.
To summarize: in general, extroverts get energy from social interaction, and introverts lose energy in them.