This is a really good question. I have made a few web services and never had a good answer. Always felt like guess work. My instinct was to try to answer this question: How expensive is the problem my product solves? You start from there and then go down because customers are not going to perceive or feel that cost equally. So even if I make a tool that could save someone weeks of work or replace some existing $500 standard solution, I may still only charge $20 for it.
I agree with the sentiment that it's better to start higher and then come down though. You really are in a sense picking your audience. This is why I am very cautious about "free" services. It isn't just the fear of how the company might actually be trying to monetize by selling my data or using ads. Rather it's fear of the sort of community attracted by the promise of free stuff.
I agree with the sentiment that it's better to start higher and then come down though. You really are in a sense picking your audience. This is why I am very cautious about "free" services. It isn't just the fear of how the company might actually be trying to monetize by selling my data or using ads. Rather it's fear of the sort of community attracted by the promise of free stuff.