Sometimes, downloaders do get a file. However, it may be a modified version of the game where the uploader has deleted vital files—such as cutscenes, music, radio stations, and multiplayer modes—leaving only the bare minimum to start a mission. Even then, the file size rarely drops below 10GB for major titles.
Compression for PS3 games generally falls into two categories: official delivery and third-party repacking. Ps3 Game Highly Compressed
Unscrupulous websites hide trojans inside repack installers. Because highly compressed games often require an .exe installer (instead of a simple .zip file), running unknown executables can infect your PC with ransomware or cryptominers that destroy your GPU performance. Sometimes, downloaders do get a file