Murray, 31, has not played at a noteworthy since Wimbledon 2017 due to hip damage that required medical procedure.
The Briton, now positioned 378th on the planet, will play Australia's James Duckworth in the first round at Flushing Meadows on Monday.
"It is a marginally odd attitude to come in with," he said.
"These are the competitions for as long as 10, 12 long stretches of my life that I've been preparing for, getting ready for and attempting to seek and possibly one day win one of them.
"It is distinctive this year as I don't have that desire."
The three-time Grand Slam champion, who is unseeded at a Slam out of the blue since 2006, has played seven matches since returning January.
He has lost three matches against Nick Kyrgios, Kyle Edmund and Lucas Pouille, all positioned inside the world's main 30.
"I'm coming into these occasions with not heaps of arrangement and almost no training - and positively no match hone," said the Scot.
"So on the off chance that I can continue advancing in the correct way and keep physically showing signs of improvement at that point there is no motivation behind why I can't get to playing at that level.
"I'm as of now rivaling them with very little readiness."
New Davis Cup 'needs a possibility' to work
Murray, who drove Great Britain to Davis Cup triumph in 2015, says the radical new recommendations to change the 118-year-old rivalry should be given a chance to work.
National tennis organizations voted for a 18-group, season-finishing occasion - supported by an organization driven by Barcelona footballer Gerard Pique - prior this month.
The choice, in which players had no say, has started outrage among a portion of the world's driving stars.
The ATP plans to organize a patched up World Team Cup in Australia in the main seven day stretch of January from 2020 - under two months after the finish of the Davis Cup finale in November.
Murray, who says he would have went without in the event that he had been given a vote, thinks having two opponent competitions leaves players with an intense choice and could be mistaking for fans.
"Something wasn't working in light of the fact that the best players were not playing," he said.
"I think there was possibly less extreme changes that could have occurred to improve it, as keeping conceivably a similar configuration however doing it each couple of years.
"However, you need to give the choice that has been made an opportunity to work and see. We should attempt to get behind it and bolster it and check whether it works.
