You can have the best vision in the world, and you would still have a blind spot. Likewise, your peripheral vision isn't that great, and your brain fabricates a lot of what it sees to remain consistent with the one thing you're looking at.
Don't believe us? Well check out this video. You'll see a series of optical illusions that play tricks on your eyes and brain.
It illustrates your blind spot, shows off the parts of your vision that aren't so effective, and reveals how the brain takes shortcuts to believe what it wants to despite what you're actually looking at.
Our brain plays a big role in what we see, and it operates in the background to be as efficient as possible. It's what makes humans good hunters, and it works by combining expectation with the things we've learned and remember.