Some of the changes, like benching Antonio Valencia, Ashley Young, Nemanja Matic and Lukaku, were likely meant to give key players a rest before Saturday's crucial FA Cup semi-final against Tottenham Hotspur at Wembley.
Manchester United now sits second in the Premier League table, but they are 16 points behind their rivals Manchester City, who have already won the Premier League title.
"If a player is phenomenal against Bournemouth, he plays the semifinal", said the manager.
"But we need to be more consistent in our approach".
On Monday, October 10, Liverpool were forced to a goalless draw by visiting Manchester United in a tension soaked encounter played at Anfield.
"So I would say, good choice". "You can't accept that [performance]".
"I know why you win, I know why you don't win". And we are inconsistent many times in our attitude.More news: Chemical weapons inspectors reach Syrian town
There is also the interesting subject of Mourinho's own future. But the fact that Mourinho has chosen to do so suggests that he feels strong enough to take the risk.
City is 16 points clear of second placed United, which can only take a maximum of 15 points from its remaining matches. Executive vice-chairman Ed Woodward is desperate for the marquee signing to succeed.
And Keown, who played 43 times for England, believes the French international's time at Old Trafford may be up.
In terms of the football, the view among the hierarchy is that winning football is entertaining football so substance, rather than style, is the requirement.
Another club expected to be involved in upheaval this summer is Chelsea. And then they showed their quality on the counter-attack. Plans for next season are so far ahead that United already have an idea of who they want to bring in as Pogba's replacement.
Pogba played a key role as Manchester United lifted the League Cup and Europa League in his debut season.
Ander Herrera was substituted at halftime against West Brom, while fellow midfielder Paul Pogba came off in the 58th minute, but Mourinho said that a yellow card had also been a factor in the Frenchman's replacement.