It might have been a mystery to Plummer why Naoupu was continually overlooked by the New Zealand selectors, but the 22-year-old has a fair idea of what has held her back.
Naoupu acknowledges a lack of application with her strength and conditioning and off-court discipline - what she terms "compliance issues" - meant she found herself in Ferns management's "bad books".
"I think the two areas I let myself down in were compliance, like not sending in my training diaries regularly and doing the extra work that I was asked to, and the other key thing for me was my fitness," she said.
To speak with such candour about her past shortcomings can only come about as a result of her more mature approach.
Naoupu said she is determined to stay in the selectors' good books.
"You learn from your mistakes. You never want to slip up, but if you do you just have to take ownership of it," she said.
Taurua, who will serve as Taumaunu's assistant coach during the Constellation Cup series as part of Netball NZ's revolving-door policy on the 2IC role, said she has seen a big improvement in Naoupu from when she arrived in the Bay of Plenty last season.
Taurua said her young charge is starting to reap the rewards from a more committed effort to her conditioning and nutrition.
"She's only just sort of realised 'holy heck, what have I been doing?'
"She has done a lot of work on herself and because of that she is starting to show really good consistency from week to week, and that's really helped Magic get [back in the play-offs hunt]."
Just as it has been at national level, goal attack has been a problem position for the Magic.
Despite having players of the international calibre of Tutaia and Brown, the Waikato-Bay of Plenty side's inability to deliver a title over the first four years of the competition has largely been put down to problems in attack.
Taurua believes Naoupu has had more impact than her more experienced predecessors as she has the ability to take an active role as a third feeder, as well as have the confidence to step up to share the shooting load.
"We've never had a shooter that can complement Irene [van Dyk] with their court-play, but also can take the shooting load as well, and that's the clear difference for us this year," said Taurua.
But can Naoupu make an impact at international level?
"She is a big game player - she loves those sort of challenges. She is also very strong, prepared to mix it up in the circle and can definitely handle the physicality."