A slow WordPress site usually comes down to a combination of things: a heavy theme, too many plugins, unoptimized images, and an underpowered environment.
Clean up your theme, plugins, and media
Remove unused extensions, cut back on heavy sliders, and compress images before uploading them. Every unnecessary plugin adds more queries and more risk of conflicts.
Check your PHP version, cache, and environment
WordPress usually runs better on an up-to-date PHP version. Caching helps too, along with hosting built on fast NVMe drives.
When do you need stronger hosting?
If a site gets a lot of traffic, runs many plugins, or handles sales, sometimes the biggest improvement comes from simply moving to a better-suited plan.