Many products have become popular because their UX design was superior than their competitors. Sometimes you may not have to have the most complicated product with many functions. A well designed knife will cut better than a knife on a multi-tool most of the time. Let’s take a look at a few examples.
Flipboard at its core is a very simple app. It is essentially an RSS reader and news app. What makes it unique is the animation and transition between articles. The experience a user has while flipping through the news is very pleasant. This set it apart from other news readers and it became very popular with the rise of iOS.
Instagram took advantage of simplicity and a single approach in order to gain popularity. Most people who use Facebook love to browse the pictures of other people. Instagram started out with only this activity in mind. Have a large news feed of photos, not everything under the sun including status updates, photos, events, etc. The experience was simple and to the point and users flocked to the app.
Microsoft use to be sole king of personal computers with nobody even close to their WIndows market share. And while they may still have the majority of the market, Apple is catching up fast with OS X, especially outside of business. Apple is doing this by creating a pleasant and easy to use UX that is not daunting for new users. Microsoft’s Windows is basically every bit as functional (some would say more so) but they are harder to use for some people and that can make a great difference.
These were just a few examples about the competitive advantage of UX design. There are many more products that I have not named but I believe this shows the point I was trying to make. Sometimes you don’t have to make a product with every function imaginable, instead focus on the experience of product use.