The Hammers chief has not yet been in charge at the London Stadium for two months since replacing Slaven Bilic in November, but already has an idea of which areas need strengthening in his current squad, with the transfer window opening for business on Monday.
The current crop of players have suffered just one defeat in five to move one point and a place outside of the relegation places.
And, while Moyes has tried to give all of the squad a chance to impress him, the 54-year-old accepts that time is not on his side and decisions will have to be made on who can depart to bring in transfer funds.
The former Everton, Manchester United and Sunderland boss feels midfield is an area which needs working on, while the squad appears top-heavy in terms of forwards.
Speaking ahead of the massive January 2 home clash against a West Brom side sitting two places and three points below them in the drop zone, Moyes said: "I'm giving players chances; I'm in a hurry, and I have to be in a hurry.
"Because of that I can't wait three or four months to see how you play.
"Everyone's shown a great desire and is committed in training, but we're short in some areas, and overloaded in some other areas."