if there isn't a product for it already, it's probably because there just isn't a need
This may be true for software packages, but it is most certainly not true for custom apps. I wish I had a nickel for every time I heard, "Now if you can get it to do that, you'd have something there." Oh wait, I do have those nickels.
you have to convince businesses or organizations they need it
Not if it's their idea. And that's where your ideas should be coming from anyway.
I knew I could make it better so that's where I happened to get my idea.
Yes! Sometimes I think the last thing said before conceiving a software product is, "Who wrote this crap?"
I know if I decided to make automatic parking garage systems, I'd at least want to hang out at some garage and shadow the workers for a few days. Not to figure out what they're doing wrong and how my software could fix it, but just to learn their job, learn what their current system does, and find out what they like and don't like about what they currently use.
This is solid gold! If you're not sure what "analysis" is, then re-read this paragraph. Better yet, cut it out and put it on your bulletin board. Everything here is necessary but not sufficient. I would follow this up with: Ask questions to everyone about everything they do, preferably in groups, until you have no more questions to ask. Get a list of every single data element you'll need from paperwork, screens, or people's heads. Don't stop until you know you've "got it".
In some markets, business customers may not want to use the same things their competitors use, and will be willing to try a new or unproven system in the hopes of getting an advantage (better productivity, lower overhead costs...). The unproven product may fail, but some are willing to try.
This is an almost always overlooked factor in buying decisions, even by the best of sales people. I don't think I've ever seen it mentioned in an article like this. Kudos to OP for bringing it up.
See? A one-person company is actually a good thing!
Addressing the concerns about a one person operation is again, solid gold bulletin board material. I love the "hit by a bus" question. (Does anyone here actually know anyone who was ever hit by a bus?)
Excellent material from someone who has been in the trenches. Thank you, Bill!