For more than four years, we have been interviewing a panel of Iranians planning and executing irregular migration. Our latest report is Refugee Integration in Europe: Life and other Plans among Iranian Irregular Migrants Settling in Europe.

More than 25% of the people we found in Iran with a plan to migrate irregularly in 2014 have now succeeded in reaching the European Union. This includes people who were not even trying to reach Europe when they first spoke with us. It is highly likely that more Iranians will attempt irregular migration in the next few years. Borders, visas and protection regimes in transit and destination countries will determine the proportion of them that arrive irregularly in Europe.

Many participants wish they had known how long their asylum processing would take. There is high demand for and supply of advice from smugglers to prove a case for protection. In some cases this is deceptive, but this is not necessarily the majority. Instead, migrants are responding rationally to the system’s demand that you stop talking about your poverty and employability; instead, you must emphasise vulnerability and persecution.

For participants now in the European Union, the two most satisfying dimensions of living in a Western country have been the least tangible dimensions: a sense of freedom and of safety and security. These feelings provide a lot of psychological support when participants face a thousand frustrations and disappointments in everyday life.

Although the physical journey to Europe is complete, participants now see a long, perhaps unending, integration journey ahead of them. Even after arriving, hope for improvement drives their thinking more than satisfaction with the present.

The longitudinal method we use underlines how important context, psychology and time are when interpreting what people mean as they answer questions and make decisions. If we were only surveying our participants now, we would draw the wrong implications about the motivations and information needs of other Iranians still at home.

For example, finding that people are ‘satisfied’ or ‘happy’ now does not tell us much about whether other people should attempt the journey. But listening to how people have changed their perspectives, what they have forgotten, and the wider context of their lives: these dimensions allow us to understand what someone back at home considering the trip may need to consider before departing. Irregular migration research – even more than other kinds of migration-related research – needs care when interpreting snapshot surveys, particularly when they are surveys of people in destination countries.