This is a short one, mainly for non-native English speakers, but true in general.
When you try to learn about a certain subject (hopefully doing research for your idea), you HAVE to know the proper terminology in the field. If you don’t know the right terms to look for you won’t find anything. This is a non-brainer, but so many people (including myself at times) just assume they know what they’re looking for and when they find nothing (because they looked for the wrong thing) they’re sure they stumbled on an untapped market..
To share the point when I fell into this trap for the first time – I once had an idea that involved Point Of Sale software. Took me about 7 hours to finally figure out it’s not called “cash register”, but POS. Every now and then I meet cool people who have great ideas nobody thought of before, just to google it and find an identical idea – as a first result. It’s just a matter of lingo sometimes.