There are a bunch of ways to measure "fast" and "reliable" and it matters quite a bit what you want your wordpress to do.
WebPageTest.org is a well regarded platform for measuring content delivery and getting suggestions for optimizing page load times.
What do you need your wordpress site to do? Where is your target audience? How big is your site going to be (how many pages, images or videos are going into the site)? How often will it be updated, and by who?
While there are things you can do to speed up content delivery with CDNs and using caching, there are some frustrating limitations to wordpress when it comes to a scaling and reliability, but it's easy to set up and to teach people how to use it.
I have found the bitnami wordpress images on the AWS marketplace are pretty easy to work with, and they've got a version to replace MySQL/MariaDB with Amazon RDS if that helps you tackle the problem of scaling for mammoth amounts of content or the hassle of tuning your database: "WordPress Multi-Tier with Amazon RDS for MariaDB".
Bitnami Wordpress is also an option on Azure and Google Cloud Platform. You can speed things up a bit by throwing more memory and cores at the problem, but you can really only overcome latency by getting your server/content close to your audience.