How do relationships cross from acquaintance to friendship?

Zat Rana thinks that friendships are based on a 'shared culture' between two people, and this culture is built through shared experiences. That belief places a pretty high hurdle on friendship. If we accept this idea, then developing and maintaining our friendships is among the most time-consuming and energy-consuming things we do. 

Design Luck: What Does It Take to Bond with Someone? 2018-Aug-4 by Zat Rana

By default, there is an invisible wall that separates us from most people that we interact with. This wall is created by the public selves both parties hold up.

The only way to truly connect with someone is to break this wall down, not fearing that doing so is going to lead to a kind of nakedness; the kind that makes us feel shame and embarrassment and vulnerability.

Once that threshold is crossed, what is left is truth and honesty and all of the soft and warm and fuzzy things that make life just a little better.

The Agency of an Interpersonal Culture: I have written before about how any strong relationship has its own culture and how much of what is great about it stays hidden in what is unspoken.... 

Every interaction between two people provides an information point to the culture that exists between them and this culture subsequently develops its own agency according to the sum of these information points.

To maintain a bond, not only do the total positive points have to outweigh the total negative points, but the two parties have to consistently redirect the agency of the interpersonal culture to aim towards a future that is meaningful before it gets too heavily reinforced in the wrong direction.

The longer a relationship lasts, the more information the culture contains and the more it affects the space that exists between the two individuals.