Who decides if youre hired?

Every round matters and you will need to pass every round. Since you are in the final round (Partner I assume), you should be close and safe to stay you have cleared previous rounds. 

If there are more candidates, then you will be compared and top ones will get it depending on number of open slots.

For Deloitte, the recruiter has no say in process once the interviews begin.

All the best and fingers crossed for you. 

It's the latter - you will be assessed based on the aggregate of all data points.

Let's illustrate with an example: 

• You can really screw up math because of nerves in one interview and do something genius in subsequent interviews in the same round. 
• If interviews were assessed individually, your recruitment journey would end after the first interview, assuming you're not allowed to fail
• By looking at the aggregate data points, however, they can identify the screw up as an outlier, because you're generally capable of doing math at an exceptional level

That being said - interviewers are still asked for a recommendation after each interview. However, one could say “don't hire” and the end result could still be “hire”, based on my explanation above.

Hope this helps! Best of luck!