This is the single most common phrase I say to developers looking to make the switch from 9 to 5 to building their own products for profit.
It usually follows the question "Why in the world would anyone pay for that?"
And of course the good news is that you are the exception to the rule.
You see most people aren't hackers. Most people can't build a todo app. Most people can't use an API. Heck most programmers can't spin up a solution to Fizz Buzz.
You are the exception to the rule.
This is good news. You have a skill that is highly valuable and can create immense value for you and for others.
So back to the original question: "Why in the world would anyone pay for that?"
It should be no surprise that the answer is that you are the exception for the rule. When many developers are making the switch from 9-5 to building for-pay products they reflect on the products they typically pay for and usually there are very few and they conclude that no one pays for products.
But if you search around the internet you'll find dozens of products that aren't complicated, but make stacks of Benjamin Franklins for the developers of those products. Of note are products like:
If you were to reduce Zapier to its very core it's essential a bunch of little scripts tying together two applications. Inevitably when we tell developers Zapier does things like send GitHub commits and issue alerts to HipChat automatically the response is usually - "I would never pay for that! I could build that in less than an hour." But when we look at our stats GitHub to HipChat is one of the most popular integrations we have.
You see, you are the exception to the rule.
Coming to the realization that people do pay for products is hard. But once you realize it the feeling is liberating.
I became a believer after hanging around other developers and business owners who would drop $50s, $100s, and $1000s of dollars per month faster than a hunger-starved cheetah chasing a gazelle on simple products when they knew it would save them time and make them money.
Once you decide to charge for a product you are going to get detractors. Often times these are other developers who you might respect. Resist the urge to follow their advice. Maintain a steely resolve. Ruthlessly test whether the market will pay for your product. Get the product in front of your core audience. Surprise yourself.
After all, you and your developer friends are the exception to the rule.