An ICP has two levels, and it's easy to write only one. The account level tells you which companies: industry, size, stage, and the trigger that makes them ready now. The persona level tells you who inside them matters: who signs, who uses it day to day, and who quietly blocks it. Each of those people needs a different message. The buyer cares about cost and risk. The user cares about their workflow. The blocker needs their objection answered before they raise it. Write both levels down before you build a single sequence. Copy written to a company gets ignored, because companies don't read email. People do.