Friends

A lot of people make friends (now, I mean the friends, one can rely on them everytime, trust them in everything and such things)  of people who they know a great lot of time. Some friends know each other since the elementary school or even longer.
On the other hand, some people know each other for long time and don't become friends. They may be just different personalities, but...
We could suppose the time is the only factor. I had thought so. Yet in Argentina I realized just how strong are shared experiences, strong experiences.
E.g. there was a woman working in NGO and traveling a lot. One could think she can't make any friendly relationships. Yet she seemed she did.
I wouldn't say the time has no importance. Many of the short term relationships just shatter after a while. But still it seems intensive experiences can do wonders.