How to choose between them
The decision comes down to one question: does your site do anything, or does it just show things? WordPress is content-management software that grew plugins to fake application behavior. A custom build with React, Next.js, or Webflow starts from your actual requirements and adds nothing you don't use.
Go WordPress when the site is a brochure or a blog, editors are non-technical, and the budget is tight. Go custom when you need booking flows, payments, gated memberships, role-based dashboards, or live integrations with another system. The wall isn't theoretical — the moment your logic outgrows a plugin's settings page, you start paying a developer to fight WordPress instead of building features.