I find that this happens when I want to do something The Right Way, but don’t have a clear path, nor the energy to figure one out.
For example I want a nice winter wardrobe, but first I have to figure out what I like, what is trendy, where to buy it, what will suit the weather. I am wholly unprepared for it. Suddenly it’s a whole ordeal, so I just wait.
In another category - art - I had to learn to be okay with suboptimal outcomes. Each attempt teaches you something, so to make good art, you have to make a lot of bad art first. Paper is cheap and making bad art is fun once you move past perfectionism.
Socialising is the same. You get better at it through practice. Practice is fun, it makes you do fun things and meet fun people.
With “shopping problems”, you are stuck with your bad purchases, your suboptimal wardrobe. Each iteration is expensive in time and money. So you try to get it right the first time. Cue weeks of research for something that is ultimately not that important. The worst is shopping problems that have an element of taste.
If someone knows a way to deal with this, I am listening.