How friendship changes over time

Friendship evolves depending on the connection you establish and maintain with the people you identify as your friends.  Also, something to consider is the stage of life you are in and the stage of life for the other person(s).  Newer/recently began friendships usually entail more quality time spent together because there is a learning and growing process.  You are gathering information about one another and determining how you want to use this information to establish the type of friendship that will be maintained.  Usually, for those that have many common qualities and interests, there is a likelihood that the relationship will last longer.  Versus relationships where there is minimal common ground may not have the same longevity. 

The age at which the friendship is established may have an impact on the evolution of friendship.  Friendships you established at a younger age may change because our brains develop over time, and the things that peaked our interests in connecting may change. That is not to say that the friendship will not withstand the test of time, but how you view that friendship may alter.  Friends that you had in grade school will always be your friends from that time, and you may seem that person from time to time, but perhaps the time spent with one another will change. 

People advance in their life stages differently than others, which changes the quality of your friendships over time.  For some, their priorities will change to spend less time with friends and more time on other life goals, like getting married, starting/raising a family, and/or growing in their careers.  That time you spend on your interpersonal goals will pull away from the time you usually spend with your friends.  This does not necessarily mean that the quality of the actual friendship will be compromised, but more just the quantity of time spent with your friends will change. 

At the end of the day, and friendship you desire to keep will require work and effort to maintain the friendship.  It will absolutely change, but how the friendship changes impact the willingness to contribute to the friendship by yourself and the other parties involved.