If one Sr. Manager or Director doesn't like you/your personality, you're out of there! I've witnessed several employees being told they're not "outgoing enough" or "too confident" for Unilever.
Further, Unilever does what they call a 360 Feedback where your Manager asks your peers/business partners to rate you. So, if you've had an difference of opinion with one of your business partners, they may negatively assess your abilities in this Feedback. This will surely make its way into your review; basically, it's the art of making people like you.
In most companies, if you're underperforming, your manager would give you at least a few warnings and perhaps help you establish a roadmap for improvement. Not here, my friend. At Unilever, they will blindsight you with a rating that signals "underperformance" at the end of the year and there's absolutely nothing you can do about it.