How does a foreign organizer agree with a potential participant in a different country? With "English" which is a foreign language for both.
Even you can fully express what you want to say, the other party understand that? Furthermore, marketing methods that are convinced by your own culture can be very unattractive or not effective for a local participant because of their cultural differences.
We, as a professional trade fair agent, know what you need and what you are marketing. We do this by communicating with our costumers in Turkish. We can "communicate" with them.
The key of the marketing success: Know the culture and language to introduce as it shall be.