Contrastive neural network models (i.e. CLIP) based image generation services (e.g. DALL-E2, MidJourney, Stable Diffusion) have shown that they can produce a huge range of flawless images, consistent with a user-provided image concept in text. While a lot of people have shared successful cases on the Internet, we still have very limited knowledge about whether such tools are helpful for daily design work. We conducted a preliminary observational study to investigate how designers create moodboards using DALL-E2. The results indicate that novice users would find it hard to find best prompts for creating and modifying generate images. The goal of this position paper is to propose potential research areas and ideas such as how to set guidelines for designing interactive image generation services for a specific purpose.