It is entire science, and at the big clubs involves dozens of analysts and hundreds of data providers.
Football is still relatively simple.. I had the fortune of watching how a good sporting director and his team were working in a club which admitteably was 1/1000 of liverpool, but the basics were still the same.. they watched loads of game on tv; but they also kept on travelling. Any player that came in; they had watched 10-15 games live; playing at home, away - different conditions..
any player that was consider to move on; they had a list of 20-30 players that could possibly fill that spot, and decisions were made swiftly..
a club of liverpool's status having a right footed midfielder and a headless chicken as left back options really tells the story..
if the new ceo praise that model as excellent without knowing it - thats bad corporate bullshit and not the best of starts..