1 Up and running fast
Laravel was build to get you up and running fast with a website with all the tools needed built in. It even comes with a boilerplate page so you literally have a website in a few seconds, although a little more time is needed to implement your necessary business logic of course.
With bootstrap, and Laravels pre-configurations of it, it's fairly easy to obtain a template and be ready in no time.
2 Tons of pre-made packages
If you want a little more logic to your website than just a cool template, and I bet you do, the deep integration of Composer and it's Packagist will make it an easy job for you to extend the features of Laravel. Want to create a newsletter? Install Mailchimp and you are ready and so on.
The great thing is that you get used to Composer just by setting up Laravel, so you will quickly become familiar with the package manager and there are literally millions of available free packages for you.
3 Custom packages
If you could't find your desired package or you want to wrap one, maybe you found an easier way to configure it, Laravel is also very handy here. Since it's deeply integrated with Composer, this means it's easy for you to built your custom logic into a package yourself and either host it public or just internal use.
Sometimes I find other vendors setup for a package too complex, at least for my cases, so I create a wrapper that pre-configures it to my needs. This way I only have to set it up once although I might use it 10+ times.
4 Target audience
Laravel was built with a specific audience in mind: Web developers. It's core is based on Symfony, but Laravel takes it to the next level in terms of usability for the developer. It's focus is solely on web applications which means it's an excellent platform to build upon.
A lot of common needs in any web applications have already been build in and more are coming all the time.
5 Attention to detail
Last but not least. Taylor Otwell, the creator of Laravel, has his focus on details to the extend where not many can follow. If you read through block comments, you will realise every line is always exactly 3 characters shorter than the line above. Methods are highly specified too, which means they never have more than 1 responsibility.
This and the huge community makes Laravel so robust.