The Baggies pulled off a transfer coup to land the England international on loan from Arsenal on transfer deadline day.
Set to make his debut at Tottenham tomorrow, Maitland Niles had interest from a host of other clubs in the Premier League.
But the 23-year-old – who often played at full-back or wing-back for Arsenal – is understood to see his future in midfield.
And being promised game time there for Albion was key to his move to The Hawthorns.
“It’s why he came to West Brom – we’re playing him in the position he wants to play, and his most favourite position,” Allardyce said. “It’s one of the reasons why he chose the Albion.
“He is a bright, bubbly young man.
“He will bring us some extra quality that I think we need.
“He is an England international who is desperate to play football which he has been frustrated about at Arsenal.
“In the position we are in, it was a big decision for him to choose us.
“His quality gives us more as a team both defensively and from an attacking point of view. Hopefully, he will help lift the rest of the players that are here – I think that’s a big thing.
“If the players that have arrived lift our performances, that will lift the entire squad. That is something I have seen over the years at many other clubs.”
Alongside Maitland-Niles, fellow new recruit Okay Yokuslu is also set to feature in an Albion squad for the first time tomorrow.
The midfielder also joined on loan on deadline day – arriving from Spanish side Celta-Vigo.
But a delay with his Visa meant he landed in England late on Thursday, meaning he is likely to be on the bench tomorrow.
“He arrived at the training ground yesterday,” Allardyce added.
“There was a bit of a delay because of his Visa.
“But we finally got it sorted – I think he had to go to Barcelona for it.
“He will be assessed to see whether he can take part against Tottenham.
“I’ll look at him in training and have a chat with him to see how he feels about being involved in the squad because the new players will be very important for us going forward.”