I heard a story recently of a man on holidays who was watching one of the locals fishing.
Expecting him to only bait and put out one rod, he watched the man take out 15 poles and place them along the waterside.
Walking over, he asked him if this was what he normally did.
"Sure do. With fifteen, I've a better chance of catching something. And if I catch more than I need I sell the rest to the local restaurant."
Makes sense you're probably thinking.
What also makes sense is fishing where there's fish, but less fishermen.
If you've got a stream that everyone's ignoring, but that you know has fish in it, you can catch what you want without any competition.
Same goes with keywords.
A lot of times you'll find authors running with the crowd, targeting the same keywords as everyone else, and fighting to make a sale.