MAFS expert John Aiken's theory on why Paul accepted the Final Task to date another woman - leaving Carina devastated

Married At First Sight expert John Aiken has weighed in on what is perhaps the experiment's most controversial relationship test – the Final Task.

In the last week of the experiment, the remaining six couples were offered the chance to go on a date with another potential match of theirs.

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Some brides and grooms were quick to refuse the task while other were lost in contemplation, but a few jumped at the opportunity to meet somebody new.

Speaking on The Official Married At First Sight Podcast with Shelly Horton, John Aiken was "surprised" by some participants' choices and revealed an interesting theory when it came to why Paul betrayed Carina's trust – and it all goes back to when they first met.

John explained the task as "a challenge of trust and boundaries" for each relationship.

The expert believed almost all of the participants would turn down the opportunity to date someone who wasn't their partner.

EXCLUSIVE: Watch Evelyn and Duncan's explosive reactions as two marriages crumble at the Final Dinner Party

"You've been through all these challenges, been through thick and thin, these intense Dinner Parties, exhausting Commitment Ceremonies where you're laying your soul out on the table," John said.

"You're that close to Final Vows – surely you're turning to your partner and saying 'I don't care about temptation, I've got you'."

Paul, Awhina, Adrian, Beth, Teejay, Jacqui, Ryan and Jamie all chose to go on the date, and for very different reasons.

John continued: "It exposed a lot of them in terms of their real connection and their intention to push forward and that was really surprising for me."

Of course, perhaps the most shocking decision was made by Paul.

He'd broken wife Carina's trust many times before but the couple were finally in a great spot in their relationship.

She'd made her boundaries very clear and labelled the task "borderline cheating".

Paul's choice to go on the date left their relationship in tatters, but John had an interesting theory as to why the groom made that decision.

John cast our minds back to when Carina and Paul first met again on their wedding day.

WATCH: Tears as one groom 'ruins' his marriage in explosive first look at MAFS' Final Vows

The couple, unbeknownst to the experts, had been on a brief hiking date eight months before but Paul ghosted Carina and the pair lost contact.

"I wonder whether this actually comes back to when he ghosted her, that he was never really 100 per cent into this relationship," John thought.

"It created a real question mark for me."

Listen to more from John, and from the couple who really kicked things off at the dinner party, in the Episode 8 of The Official Married at First Sight Podcast.

The Official Married at First Sight Podcast is available now, so subscribe wherever you get your podcasts.

On Apple, click here, or on Spotify, click here.

You can also watch the podcast episode exclusively on 9Now.

Married At First Sight continues tonight at 7.30pm on Channel 9 and 9Now.

Stream every episode of Married At First Sight for free on 9Now

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