There is a specific kind of friendship that feels, from the outside, like an ideal: no arguments, no serious tensions, no difficult conversations. Years of warmth without friction. These are the friendships that get described as "easy" — and they are, in a particular sense, easy. They are also often limited in ways that don't get named, because the limitation is invisible by definition.
The conflict you have never had with someone is not necessarily a sign that there is nothing to conflict about. It is more often a sign that one or both of you has decided, consciously or not, that the friendship cannot hold what a conflict would require. The avoidance is a form of tacit agreement: we will not test this, because we are not sure it would survive the test. That agreement may be provisional — we haven't had a reason to test it yet — or it may be structural: the relationship is organized, below awareness, around the mutual project of not finding out.
What this costs is difficult to measure precisely because what's absent is by nature invisible. You don't know what you would have learned about this person if you had disagreed with them about something that mattered. You don't know what they would have learned about you. You don't know whether the warmth that characterizes the relationship rests on genuine compatibility or on the careful mutual management of any territory where incompatibility might appear. You don't know whether this person, who has been kind and present and generous across a long friendship, would be fair in conflict — because you've never seen them in one.
Some never-conflicted friendships are genuinely the result of profound compatibility. Two people who share core values, have navigated similar life situations, and whose communication styles happen to mesh will naturally produce fewer friction points. The absence of conflict is not, in these cases, the result of avoidance; it is the result of genuine alignment. The problem is that this is genuinely indistinguishable from the avoidance version from the outside, and often indistinguishable from the inside as well.
The price of conflict avoidance in friendship is paid in several currencies. There is the price of range: the friendship becomes confined to the territory that feels safe, which is often smaller than you realize until you notice a topic you've never gone near. There is the price of honesty: you develop a mild but consistent practice of editing yourself, saying the slightly adjusted version of what you think rather than the actual version, because you have learned what this friendship can hold. There is the price of knowing: because you've never been in conflict with this person, you don't actually know who they are in conflict, which is a significant gap in your knowledge of someone you call a close friend.
The most significant price is the price of depth. Depth in friendship is not the same as duration or frequency of contact or shared history. It is the quality of mutual knowing that comes from having been through something difficult together and survived it. A friendship that has only been tested by pleasant conditions has not yet demonstrated that it can exist in the full range of human circumstances. That is not automatically a problem — many friendships have a more limited scope and are none the worse for it. But if the friendship claims to be more than that, if it is carried in your life as one of the deep ones, the absence of conflict is relevant information about that claim.
None of this means you should manufacture conflict. But it is worth examining: what is the friendship protecting? What would happen if you disagreed directly about something you actually disagree about? The answer might be: nothing much, the friendship is more robust than you've given it credit for. Or the answer might be: you'd find out something important about both of you that has been obscured by the mutual project of getting along.