Advocates of JAMstack (JavaScript, APIs, and Markup) claim that it provides improved uptime, speed, and security compared to traditional server-installed website applications.

Uptime: Because JAMstack websites are served as static files, they can be easily distributed across a globally distributed network of servers using a content delivery network (CDN). This makes them highly available and resilient to server outages or failures.

Speed: JAMstack websites are fast because they are served directly from the CDN without any server-side processing or database queries. The lack of server-side processing also reduces latency and improves the overall user experience.

Security: Since JAMstack websites do not rely on server-side code, there are fewer potential attack vectors for hackers to exploit. Additionally, since there is no server-side code running, there is less risk of vulnerabilities due to outdated software or misconfigured servers.

However, on the other hand, there are also reasons why some people prefer server-installed website applications:

Flexibility: Server-installed applications offer more flexibility and can handle complex dynamic content and interactions. They can also be easily scaled and customized to meet changing requirements.

Ease of use: For people who are familiar with server-side programming, server-installed applications may be easier to work with, as there is a wealth of existing software and tooling available.

HOWEVER, you are swapping ease of use for speed and security, in most cases.

Integration: Server-installed applications can easily integrate with other software and systems, such as databases and content management systems. This makes it easier to manage and update content and data on a website.

HOWEVER, you are swapping plug + play integration for plugin support and maintenance.

In conclusion, the choice between JAMstack and a server-installed website application often comes down to the specific requirements and constraints of a project. Each approach has its strengths and weaknesses, and the right choice will depend on the particular needs of the website or application being built.