Great customer experience is immensely important to brands It can either create or depress sales. The feel a customer gets from your site goes a long way in terms of sales, repeat business, referrals, and overall brand reputation. A solid visual design is important but if your site is slow then this can become frustrating to the customer and have negative effects on revenue and your brand. If you are looking to reduce friction between users and your website then the JAMstack is perfect for you.
Servers have been used to build pages on the fly but why wait for a server when you can generate them at deploy time? When it comes to minimizing the time to the first byte, nothing beats pre-built files served over a CDN.
With server-side processes abstracted into microservice APIs, surface areas for attacks are reduced. Customer data and security is important and with no direct connection to your server you are mitigating risk.
When your deployment amounts to a stack of files that can be served on multiple channels, scaling is a matter of serving those files to more places. CDNs are perfect for this and often include scaling in all of their plans.
Loose coupling and separation of controls allow for more targeted development and debugging, and the expanding selection of CMS options for site generators removes the need to maintain a separate stack for content and marketing.