1. Limitations of CSS media queries.
Responsive web design relies heavily on CSS media queries to be compatible on a wide range of devices. However, most mobile devices are not compatible with CSS media queries.
2. Image Resizing.
Responsive web design resizes images to the mobile device’s screen. The full image is downloaded on a mobile device and resized to fit the screen. This consumes unnecessary CPU and RAM.
4. Mobile needs and desktop needs may be different.
Responsive Web Design resizes the website to fit the device and does not use key mobile features like the geolocation, gestures, hardware limitations, etc. as those features are not available on desktop devices.
5. Mobile versions are always more optimized.