Google search is your biggest lead source
Wix sites consistently underperform custom sites in local-pack rankings — speed is one factor, but limited schema control and URL structure are bigger. A Sarasota dentist on Wix loses to a custom-coded competitor in the local pack, every time, all else equal.
You want to be cited by ChatGPT / Perplexity / Claude
AI search engines weight schema markup, llms.txt, and entity-rich content heavily for citation. Wix's limited schema implementation and inability to publish a proper llms.txt makes AI citation unreliable. Custom-coded sites are built for the AI search era from day one.
You're scaling beyond a brochure site
Custom forms, integrations with your CRM, scheduling systems, member areas, conditional content — all of these are doable on Wix but they push you into Wix's Velo platform, which is essentially a programming environment with worse tooling than just hiring a real developer.
You don't want to be locked in
A custom site can move from Hostinger to AWS to Cloudflare to anywhere with PHP support in an afternoon. A Wix site is on Wix forever; exporting is functionally not a thing. Vendor lock-in is real cost.