Pilot implementation is a method for avoiding unintended consequences of healthcare information systems. This study investigates how learning from pilot implementations is situated, messy, and therefore difficult. We analyze two pilot implementations by means of observation and interviews. In the first pilot implementation, the involved porters saw their improved overview of pending patient transports as an opportunity for more self-organization, but this opportunity hinged on the unclear prospects of extending the system with functionality for the porters to reply to transport requests. In the second pilot implementation, the involved paramedics had to print the data they had entered into the system because it had not yet been integrated with the electronic patient record. This extra work prolonged every dispatch and influenced the paramedics' experience of the entire system. We discuss how pilot implementations, in spite of their realism, leave room for uncertainty about the implications of the new system.