Mark and Andrea have been seeing each other for a few months. Things are going well — better than well. Tonight, at Mark's flat, things are supposed to go further.

They don't.

After the build-up, Mark can't maintain a firm enough erection. He apologises. He says this has never happened before. He tries to salvage things. Andrea says: "Don't worry, these things happen." A brief kiss. Then a minute of quiet, both sitting on opposite sides of the bed, staring at the floor.

Here is what Mark is thinking: some version of I've ruined this, What's wrong with me, This is humiliating, It'll be the same next time, Andrea will leave me.

Here is what Andrea might be thinking — and this is where it gets complicated. Because Andrea's thoughts aren't one thing. They might be it's my fault, I'm not attractive enough, he doesn't want me. Or they might be he needs to sort himself out, this is his problem. Or, depending on Andrea's own history, he must be seeing someone else. Somewhere in between, in the vast middle ground, are dozens of combinations of doubt, insecurity, and meaning-making that have nothing to do with what actually happened.

What actually happened is quite simple. The penis had been made the instrument of proof — the engine through which desire, attraction, and feeling were supposed to be demonstrated. That is not what it is built for.

Sex is not a performance. It is an interaction — and at its most essential, a form of communication between two people. The moment it becomes a test with criteria to meet, it stops being either of those things. What remains is an audience of one, a set of expectations, and a body that was never designed to perform on command.

An erection is a physiological event. It requires a specific state of the nervous system to occur — one that is fundamentally incompatible with being evaluated. Not because you're weak, or broken, or because something is permanently wrong. Because your body is working exactly as it was designed to: it will not perform, but it will communicate, when the conditions allow it to.

Why it works alone but fails with someone you care about

When you're by yourself, the stakes are usually lower. For most persons, the body isn't being evaluated — there is no audience, no possibility of disappointing anyone. The nervous system stays in a parasympathetic state — calm, open, receptive — and blood flows into the penis the way it's supposed to.