The winger has agreed an extension to his loan deal with SPFL Championship side Morton that will keep him at Cappielow until the end of the season.
After struggling to make the breakthrough into Ally McCoist's plans this term, McKay impressed during his initial one-month switch to the Ton.
And the 19-year-old admits the lure of first-team football was too hard to turn down after signing on the dotted line in Greenock for a second time.
McKay told SportTimes: "First-team football was a big factor in my decision. I really want to play and need to be playing at my age.
"I am happy at Morton so there was no point going back to Rangers and not getting a sniff.
"If I am out playing games then it will benefit me and Rangers in long run. When I go back to Rangers, I will return a better player.
"I went in and spoke to the manager (McCoist) and he was happy for me to stay out on loan and play first-team games.
"He never said that I wouldn't be getting a chance at Rangers. But I know he has brought in a lot of good players and has a big squad.
"I haven't had that many opportunities up to this point. Coming back to Morton is a chance to get the game time that I need and that is what is important.
"The Championship is obviously a league above where Rangers are just now and I am going out and challenging myself and getting experience in this division.
"When it comes to next season, I will already have played in the Championship so hopefully that will help my chances of playing for Rangers.
"Hopefully I can keep playing for Morton, keep improving and become a better player."
McKay won rave reviews for a series of superb showings in his breakthrough season at Rangers last term but has found it tough to hold down a jersey as the Third Division champions have raced into a commanding position in League One.
He is set to make his second Morton bow when they face Queen of the South tonight and the forward is determined to play his part in keeping the Cappielow club in Scotland's second tier.
McKay said: "I am happy to stay at Morton until the end of the season.
"We are improving in every game but it took a few games for us to get the results. We have got a couple of points now and the boys are playing well.
"I wanted to stay and help Morton stay in the Championship.
"Hopefully we can get another victory against Queen of the South and look to climb up the table."
After committing his short-term future to Morton, McKay will spend the coming months under the guidance of former mentor Kenny Shiels.
The pair worked together during McKay's formative years at Kilmarnock before he was released and clinched a deal with Rangers.
And he is confident the Northern Irishman can bring out the best in him between now and the end of the season.
He said: "It is good to be playing under Kenny. I worked with him at Kilmarnock and he has still got his philosophy about playing good football."
Meanwhile, Rangers chief executive Graham Wallace was today reported to have turned down a £900,000 offer from Nottingham Forest for full-back Lee Wallace.
It is understood the bid is well short of the Ibrox club's valuation of the Scotland internationalist. However, an improved offer in the region of £1.5million may be considered.