A question about a recipe: Yam, Zucchini, and Chickpea Salad

I have a question about step 5 on the recipe "Yam, Zucchini, and Chickpea Salad" from Rivka. It says:

"In a small bowl, combine tahini, lemon juice and zest, olive oil, and half of chopped garlic. Add water by the teaspoon until the dressing is smooth and runny. Taste, and add additional chopped garlic if necessary. Add salt and pepper to taste. Pour over vegetables, toss to coat, and serve warm or room temperature."