When I'm on the range, one of the things I assess when evaluating a new-to-me shooter is her relationship with her gun. I'm not talking about whether the gun has a cute name or a fancy paint job, or if it travels gently cocooned in an expensive case. Instead, I look for the shooter's comfort level with basic gun operation: does she hold the gun naturally and not like she's afraid of it? Can she load and unload the gun without awkwardness? Does she know how to rack the slide, work the bolt, (dis)engage the safety, and otherwise use the controls on the gun with confidence? Or, as one of my instructors phrases it, does she have instinctive gun handling skills?
Notice that speed isn't on the list. That's because I'm more interested in knowing if a shooter is comfortable enough with her gun that her attention isn't taken up by the manual of arms. Seeing that kind of proficiency helps give me assurance that a shooter won't be so distracted by fumbling with a reload or clearing a malfunction that she'll forget to be safe. Notice too that I'm not testing shooters on their ability to speed field strip a gun (blindfolded, behind their backs - neat party trick though) or to explain how every spring and lever in the gun interact. While learning those mechanics over time can be useful when delving ever further into the shooting world, they probably won't be a factor on the range under most circumstances.
More importantly for a shooter, instinctive gun handling is one of the set of skills that, once internalized, gives her the freedom to concentrate on other aspects of shooting, whether it's running through a fast and furious action pistol stage or intensely focusing on putting the perfect group of all X-hits through a long-range rifle target. Having those instinctive gun handling skills are an important part of meeting your goals as a shooter because those skills allow you to improve the end result of pulling a trigger as you focus on the shooting itself instead of getting hung up by the tool in your hands. Like driving a car, navigating slick roads isn't quite so hard if you don't have to think about how to shift gears or turn on your windshield wipers.
It doesn't hurt that being clearly competent with your gun makes you look like a beautiful, bad-ass shooter too.
