The search for a Windows 8 highly compressed repack is usually driven by two things: limited internet bandwidth or very low disk space. While "highly compressed" versions can shrink an OS installer significantly, they come with trade-offs in installation time and system stability.
In short: Yes, with almost no exceptions.
Pros and Cons of a highly compressed repack of Windows 8: windows 8 highly compressed repack
Even if you own a legitimate Windows 8 license (a retail key from 2013), installing a repack breaks the EULA because the binaries are altered. Your key will be rejected during activation.
Conclusion
Unattended Installation: Most are configured to skip the product key and user account setup screens for a faster, one-click installation. Important Considerations
Because these files are "super compressed," the installation process can take significantly longer (often 1.5 to 6 hours The search for a Windows 8 highly compressed
Repacks often shrink the standard Windows 8 installation (which typically requires 16 GB to 20 GB