This can be depressing unless you realize and are prepared for it. When the artist returns home, the experience results in many new ideas to use in subsequent paintings. Sketches and small studies can be used to produce good work once you are in your own studio. Keep a painting journal, if possible, and make notes on the teachers' instructions and your own experiments. A change in scene often calls for a change in approach.
Some locations call for a completely different palette of colors.
You should realize this before you decide what paints and supplies to take with you. Try to take materials for every possibility. Often there are not art supply stores nearby. Those who attend workshops frequently often collect experiences as well as painting ideas. The after-workshop adventures with new friends can be at least as memorable as the new painting techniques learned.