WebP has an excellent lossless image compressor (like PNG just 25-40 % more dense), but the lossy format has weaknesses that people focused on, and slowed down

WebP has an excellent lossless image compressor (like PNG just 25-40 % more dense), but the lossy format has weaknesses that people focused on, and slowed down the adoption. The initial lossy encoder had weaknesses in quality -- it had bugs or was a port of a video coder. Nowadays, the quality is much better, but the format forces YUV420 coding (does not allow YUV444 coding) which limits the quality of colors and fine textures.