What you CAN do is take someone's idea and focus it very heavily in a single market or vertical. Provide options that that the original innovator can't/won't do.
For example, for all of the great web-based services that exist, very few of them are actually prepared to adequately serve highly regulated/restricted markets like medical/legal/nat.security/etc.
If you made a Gitub that does a great job of dealing with compliance in any of those one fields, you just might have a niche. And it might be a niche that Github didn't want anyway. (this is just an example, for all I know, github does a great job in these areas).
The best part is that you have an opportunity to innovate....yay YOU!
Find a second-story window and jump out of it. If, in the next hour, you aren't in the hospital or morgue, CONGRATULATIONS!!! you're now into Parkour!.
For example, for all of the great web-based services that exist, very few of them are actually prepared to adequately serve highly regulated/restricted markets like medical/legal/nat.security/etc.
If you made a Gitub that does a great job of dealing with compliance in any of those one fields, you just might have a niche. And it might be a niche that Github didn't want anyway. (this is just an example, for all I know, github does a great job in these areas).
The best part is that you have an opportunity to innovate....yay YOU!