Drupal is the most trending thing now because of it's Usability, Security, Customization Options, Cost effectiveness, Size, SEO and Who uses it. Latest Drupal release which makes it very powerful and beautiful.
Drupal is satisfying very wide range of requirement and there few points which very important. You can Develop any kind of website in Drupal simple one page website to 1000000.... of pages website, high security websites like large enterprises, complex web development, government websites and Drupal is the first choice for government websites.
1. Usability - This is very important thing after product is finished how easy this is to use if you have limited knowledge of website development. So in Drupal a developer have an option and most important thing everyone can't make it easy to use, but who knows Drupal way they can make it the way so that it could be user friendly. As a editor or author you can easily edit any part of the page after one click, Because Drupal is providing modules to enable editor into textarea so this is making it easy to edit any content. But finally Drupal is providing an option to make it user friendly. So in Drupal we have option's we just need to use.
2. Security - This is most important thing that your website shouldn't be hacked or stolen any important data either it will create great trouble to you. Drupal has enterprise-level security and provides in-depth security reports. That's why many government websites are using it. Drupal community is always releasing security updates time to time which is always required to be updated. So this part of Drupal will make you safe and give belief to use it.
3. Customizing Options - When i was talking about Usability so i said that Drupal have an options to make it very user friendly so here Customization options comes. Drupal is providing an option in order to make it like your design according to your functional requirement and it could be achived using custom theme and modules.
4. Cost - Drupal Developers are costly than other cms developer's but important thing is, what you want? do you need better security, better usability and performance or cheaper product. Here you need to take very wise decision because when you finaly getting your product or website in production environment major things are performance of your website, is that secure? because your earning, user's faith totally depends on those factors. So in this case Drupal is cheaper than any other cms in web world.
5. Size Issue - When it comes to size issues Drupal is the best CMS ever, Drupal can support anything from a one-page static site to something that has thousands of pages and thousands of readers reading those pages simultaneously.
6. SEO built - Search Engine Optimization isn’t platform specific but there are a few tricks that make one better than the other. But It has been said that Drupal has been built specifically to be search engine friendly. It has bunch of modules which you can use which will help you to make it better and better for SEO. For better seo page loading is very important thing and here Drupal have it's core caching technique also it has other contributed modules which can make any kind of website load faster than build by other cms.
7. Multiple Roles - It has an option to create multiple roles and grant permission which desired for those roles. Also it has option to create custom permission and there several contributed modules which make it better and better when it is required very top level permission.
8. Who Uses Drupal System? - The White House and The Economist because Drupal is good for those who need a stable and scalable website. First choice of Developer's is Drupal because it is powerful and flexible, so they can work their magic on it and create their own solutions.
For more information on Drupal 8.x please follow this link