The former West Ham defender, who now works as a pundit, made the comments following the Hammers’ 1-1 draw with Stoke City at the London Stadium in the Premier League on Monday evening.
Moyes’s side needed a late goal from Andy Carroll to rescue a point from the encounter.
Hernandez did not start the match, but the former Manchester United striker came on as a substitute in the 76th minute.
The 29-year-old joined West Ham from German club Bayer Leverkusen in the summer of 2017.
The Mexico international striker has made 16 starts and 10 substitute appearances in the Premier League for the London club so far this season, scoring eight goals in the process.
Hernandez has often been deployed out side and has not been given a long run in the team in order to score goals more regularly.
That decision by Pep Guardiola on Joe Hart becomes more and more justified with each game. Coulda been a costly error tonight but that point and one more win should see #WHU safe and when that happens... problems need to start being addressed.— Daniel Gabbidon (@Gabbidon35) April 16, 2018
The whole Henrnadez signing has been laughable really. I said start of the season if u go down that route u must have a specific plan with the ball to get the best out of him, instead the best finisher at the club has either been played wide or benched!— Daniel Gabbidon (@Gabbidon35) April 16, 2018