I think many folks had some early "goldfish in a bowl" experience, or something else that ended badly, suggesting aquariums aren't easy to keep. Then later seen someone else's beautiful aquarium (esp. saltwater) that cost thousands of dollars, suggesting any decent aquarium is expensive.
I was under these impressions for a long time. My family never had more than a goldfish in a bowl. Even though aquariums fascinated me I never actually thought to actually try it until nearly 30 years of age, and only then because I was given a nearly complete setup for free. If it hadn't been for that I might have never tried.
And I admitted to myself I knew absolutely nothing about it, so I sought out my own information. Some "Freshwater Aquarium FAQ", which covered the nitrogen cycle, feeding, water changes, chlorine/chloramine, all the essentials in 20 pages or so. Everyone should read that or something like it when they start, at their own leisure, not rely on a quick conversation with someone.
The fact that 10 years later I'm still making progress, and always have a list of things I want to try extending at least a year into the future, definitely helps keep this hobby foremost and fresh; despite numerous others competing for my time.
Plus I always tried and failed to keep houseplants, either over- or under-watering them. At least here I don't have to worry about that. If the tank is full, the plants have the right amount of water.