The problem is that while the human can give some rationalizations as to “ah, this is probably why the computer says it’s the best move,” it’s not the original reasoning that generated those moves as the best option, because that took place inside the engine. Some of the time, looking ahead with computer analysis is enough to reproduce the original reasoning—particularly when it comes to tactics—but sometimes they would just have to guess.
The problem is that while the human can give some rationalizations as to “ah, this is probably why the computer says it’s the best move,” it’s not the original reasoning that generated those moves as the best option, because that took place inside the engine. Some of the time, looking ahead with computer analysis is enough to reproduce the original reasoning—particularly when it comes to tactics—but sometimes they would just have to guess.