I experienced it on myself. As soon as you start thinking about making money, the flow of creativity stops. I don't know how to finish a particular design or start a new one anymore. And I don't experience joy. My mind obsessively engages into thinking through ways of getting into the market, putting together an online shop, brought to "perfection", producing items "people will like", and so on and on. I become restless, deprived of energy, strength, and time. I don't feel satisfaction from my design anymore, and look at the items I have to complete, as though it's some kind of chore I have to but don't want to do. Strangely enough, all this thinking and struggling takes up enormous amount of time and energy, I feel definitely sick and cannot even find time for my family and myself. And when I finally realize that I slipped down and need to wake up, the recovery takes still more time.
The strangest thing though is that although the primary reason for all this "money thinking" is desire to grow your business however microscopic it may be at the moment and creating a "perfect" environment for working, connecting, sharing and designing, it doesn't lead you anywhere. In my experience it only leads to stress. It becomes sort of Mirror of Erised from J.K.Rowling's wizarding world, you see yourself prosperous, but don't know how to get there, and so you stay there, staring at the image in the mirror waisting your time and your mind. Apart from being unhealthy mentally and physically, too much of "money thinking" throws you back down the road of your development as an artist-designer, you loose access to indefinite source of creative ideas. And the energy you put into your creations is not exactly the same as you intended in the first place.
After experiencing this for several times, my knowing is that your creativity is your primary and starting point of everything else. You bring into the world that which comes from your deepest place and makes you happy, you bring that to life, that only truth, and the rest comes to you as a natural consequence. Guard your peace, always. And remind yourself often, that whatever you are doing now that feels right, is already bringing you closer to whatever you desire.
And as for something "people will like"..., I always felt deep down that you never have to adjust yourself to some kind of conventional need, or popular demand, or current trend, or whatever. Do what truly comes from your desire to create, offer it to people and the trend or fashion may change.
Share with me if you've ever had a similar experience. And thanks for reading.