Is solar hard to sell?

I'm curious to understand, is solar energy really a difficult product to sell in today's market? With the growing concern for sustainability and the environment, I would have expected solar systems to be in high demand. Yet, I've heard some claim that it can be a challenge to convince consumers of its benefits. Could you elaborate on the factors that might make solar a harder sell than other renewable energy sources, and perhaps offer some insights into how to effectively communicate its value proposition to potential customers?