I've been involved in 10-pin bowling for most of my life. Except for a 5 year span where I lived in a city that didn't have a bowling alley at all (until they made one that only lasted a year or two because no one was interested) I have been bowling rather regularly since before I could legally drive.
People tend to attach a great deal of importance to strikes but honestly, spares are where you really can shine as a regular bowler.
src
Anyone can get strikes. The internet is awash with people who don't even have any idea what they are doing getting strikes. Strikes are indeed a major part of the game and if you get them it obviously boosts your score a lot because it is 10 pins plus whatever you get on your next 2 rolls. However, unless you can bowl consecutive strikes, there really isn't any massive benefit to getting one.
Spares on the other hand are the sign of a bowler that actually has control over their game because it's easy as hell to hit pins when the entire lane is filled with them but hitting just one or two pins in that massive area requires a great deal of skill, especially if there is a bunch of space between the ones that remain after your first roll.
src
This is called a "baby split" and it is one of the easier ones to clean up in bowling. There are two ways of accomplishing it: You either hit the 3 pin to the left bounding it into the 10, or you hit it on the right with a light roll so that it pushes the ball towards the 10. There are of course far more difficult splits out there and some of them, like the dreaded 7/10 split, is damn-near-impossible to achieve.
A spare gives you 10 points plus the pins you get on the next ball and if you are a decent bowler, this is likely going to end up being 7-10 points hopefully resulting in another spare at the end.
I see it time and time again in our bowling group here in Vietnam: People get all worked up over a strike that they got by sheer luck, and then proceed to do almost nothing on the next two balls. Accuracy is key in bowling and being able to hit single pins or two pins standing alone is harder than getting a strike in my book.
src
Despite what it appears like from your end of the lane, the pins are actually quite far apart from one another and a lucky roll can result in a strike even if you miss the "pocket" by a great deal. I've seen strikes where people missed all 3 of the headpins just by crazy domino effects that sometimes just happen. This is never going to happen if there are just a few pins standing.
So for all you bowlers our there, if you have access to more advanced lanes that can be programmed to set you up with racks of baby-splits over and over rather than just racking all 10 pins every time, I think this is a fantastic way to improve your overall accuracy.
After more than 30 years of bowling, I have come to the conclusion that accuracy is far more important than power or ever those weird styles of bowling that people sometimes implement in order to get a hook on the ball by spinning it.
Obviously you want to get as many strikes as possible, but once you have the ability to hit any pin anywhere on the lane, hitting the front 3 becomes easier just by nature.
I regard people that can pick up spares a lot more than the person who gets 4 strikes in a game that are all spread out and their scores are not going to be as good as the person that can pick up spares on a regular basis. This game is all about not leaving any open frames, not just getting strikes every now and then.