Machines and functional fitness?

What role can machines play in functional fitness? We often tout the advantages of no-machine training, but machines can play a role. “Isolate then integrate” is an important concept for anyone looking to strengthen a weakness. Sometimes compound movements hide muscle weaknesses by allowing stronger muscles to dominate the movement at the expense of the weaker muscles. Machines isolate muscles, allowing you to focus on them, making weaker muscles stronger. Then when you go back to compound movements, the weaknesses in your kinetic chain are stronger. Plus, machines can hit angles that compound movements miss. Finally, the ability to isolate muscles is useful when something like your lower back is sore and compound movements are therefore out of the question. So used smartly and not as your main fitness tool, machines are useful.