Many people talk about wanting to make new friends, but the fact is you really need to make time to get a friendship off the ground.
Established friendships can go through periods where people are busy and don't have time to devote to one another. At the same time, they can call each other up when they do have time and reconnect in a moment. They don't need to constantly nurture their friendship in order to keep it alive, because they've been pals a long time and have probably already done the hard work to bond for the long haul.
However, new friendships are fragile and can be easily derailed if the proper attention isn't paid to them.