A client's WordPress site had a favicon that worked fine in Chrome desktop tabs. But when I bookmarked it on my iPhone, it showed a gray placeholder. On Android, same thing. Windows 11 taskbar pin — blank. The developer had uploaded one 32×32 PNG and called it done. I replaced it with a full favicon package from our multi-size generator and every platform rendered correctly within minutes.
WordPress lets you upload one "Site Icon" in the Customizer — 512×512px. It crops this down to a few sizes automatically. What WordPress does not generate: Apple touch icons for iOS home screen bookmarks (180×180px), Android PWA manifest icons (192×192 and 512×512), Windows tile pins (150×150), or a monochrome SVG mask for macOS Safari pinned tabs. Generate all 12 sizes in one batch →
The entire process takes under five minutes. I have done this for 40+ client sites and never had a favicon complaint since.