Flexibility in the field

Going to Athens, I had a set plan to study tattoo artists and the culture of tattoo artists in Athens. Unfortunately this did not work out for me, as the tattoo artists were not responsive, and did not want to cooperate with my research. Two weeks into the fours weeks, I had to switch topics. Although difficult, by keeping flexible and staying open, I was able to make contacts and research. It also allowed to me to conduct field research without a goal in mind, which gave me a new mindset about anthropological studies.

Is it ideal to conduct research without a set of questions and goals?
What else can be done in the field when there is lack of trust and rapport?