Exact same flight time outbound and inbound

[Edmund]

I noticed something peculiar, and I'm wondering how often this happens.
Iberia flight IB6833/IB6830 on 01 and 03 Aug 2020 took exactly the same time going out and returning.
(Madrid-Santiago-Madrid. Flight time both ways: 12:24. Aircraft - EC-NDR, A350-900)
Most flights goes faster west to east so I don't think this happens very often.
Would like to hear your thoughts on this.

[aerospace100]

Usually West to East is faster due to the prevailing winds however the strength of these tailwinds varies a lot. It's also possible that on the return leg, the pilot wanted to make up time due to a delay.