Here are some features Twitter DID NOT have when it began in 2006.

- Search
- Mentions
- Replies
- Retweets
- Lists
- Permalinks for tweets
- An algorithm

All of these features came when users demanded them.

The search function was actually built by folks who didn't work at Twitter. It was a service called Summize that eventually got acquired by Twitter and integrated into the service.

Retweets started when users began sharing other people's tweets by adding an "RT" before the text.

@vimoh I am sure it took you a lot to analyse how Twitter has evolved. I think we all have a tint of our understandings and experiences of the past that comes along with us. For information isn't the problem, it is the obsession that's a problem. And also "should" is a big problem. Expectations somehow hinder exploration. These are purely my personal thoughts.
@musafir Not sure I understood what you mean, but I appreciate the sentiment. :)