[halomru]

>there are no algorithm changes (otherwise the results would be different

Insertionsort, Mergesort and Timsort are three wildly different algorithms with different speeds, but on every possible input they produce the exact same result

[sjolsen]

Strictly speaking, it's possible for different sorting algorithms to produce different results if you sort using a weak order rather than a total order.

[cmrx64]

Or an unstable sort (which none of grandparent's examples are, but aren't uncommon in naive implementations)