If you can imagine yourself thumbing through an old card catalog system at your local library, you'd find that there is a certain quality to the system. Every book is cataloged according to a numerical system called the Library of Congress cataloging system. And you see all the same basic information with every listing. It's designed that way on purpose.
While the Internet is certainly not your public library (and much of the information you find online is suspect), in terms of finding the information that you want to find, there is a quality system built into the search engines where people go to search for information.
Each search engine has its own quality guidelines, but the leading search engine - Google - sets the standard. You can learn more about Google's quality guidelines on its website.
Bing, the No. 2 search engine online, also has its quality guidelines. Note that they're not a great deal different than Google's.
While there are similarities to the quality guidelines, there are also subtle differences. That's why website owners will often find their web pages doing well in one search engine while not doing so well in others. But you also have to consider the level of competition. For almost any niche there is quite a bit more competition for Google search rankings than for search rankings at any other search engine - even at Bing.
So what should you make of this? As the owner of a business who is trying to get your web pages to rank for your key terms, it's important to know the search engine guidelines and to abide by them. There are penalties if you do certain things wrong. And the rewards for doing all the right things right include higher rankings, more targeted traffic to your website, and more revenues from good landing pages that close the sale.