Here are a few principles that i have learned from reading about Apple.
Apple: keep it simple, keep it human, do a few things great, brand bank
Keep it simple: get rid of anything that will distract and is seldom used. Other operating systems, computers or phones can have more features, more slots and more bells and whistles but apple has done a great job of eliminating those things that are not used as often or are not as important. They have less disk drives or slots than many other computers. Less buttons on many of the devices. Less ability to change the battery or do updates. Allowing these things comes at a cost and they believe that if the feature is not used often enough or is not important enough it is better to leave it out.
Keep it human: make sure to think about what humans want and not just what we can add. Think about how the customers use the product and design for that, not just extra features because we can. One other aspect is thinking about benefits that people get, not new features. People care about the benefit and the feature is just a means to the benefit. Apple says “1000 songs in your pocket” and not 5 gigs. Think benefits, not features when marketing to what humans really want.
Do a few things great: do not attempt to be the best at everything. 2 desktop, 2 laptop, pro and home use, not 30 variations like Dell. Apple now has more products but they still keep it very focused at what they can do best. The famously say they can display all of the products they sell on one kitchen size table. They are not creating 15 different phones and 15 different laptops, 15 printers and so on. They focus on a few products and just do them better than anyone else.
Brand bank: think of your positive brand reputation as something you can add to (do something good) and take deposits out of (do something bad). If you take too much out you will go broke. People will not have a positive feeling about your brand but if you do a great job most of the time you will be able to mess up once in a while.