1. it has to look and behave the same way everywhere (because we don't want to have to retrain users when they switch platform, to maintain several documentation and marketing materials, and because we want to respect the designer's esthetic vision, and / or corporate graphical vision)
2. It has to look and behave native everywhere (because we don't want to confuse users of any given platform.)
Again : of course, I know they're contradictory ! If you have a sword to cut that knot, go for it !
And of course you're perfectly allowed to value requirement 2 more than requirement 1.
And sadly here, different user's interests are not aligned with different software producer's interests, so we're basically not going to please everyone.
Again, I have neither data, nor religion, nor solution about this.