Some equipment has many different modes, settings, accessories. For each of the tests in IEC 60601-1 we could test all modes/settings/accessories, but that would take a long time. So, the standard allows you to select the worst case.
In the past this was done by the test laboratory, but actually they often don't know the worst case conditions.
So in IEC 60601-1:2005 then required this to be documented in the risk management file, but it does not really fit risk management. It's really just engineering judgement, and needs to be considered for each test individually. What's worst case for leakage current might not be worst case for temperature test and so on.
So in Amendment 1, it's reverted to a record that needs to be kept for each test (see Clause 5.4).