Some people get a lower score on step2ck than step 1. The reason for that is almost always that they studied less. For some residencies all you need to do is pass step 2 so people will study a lot less for it. In other situations, people dont take step2ck until after match is completed. If someone is already matched, then all you need to do is pass step 2ck.
In other cases, people really go all out for the step 2ck and those people tend to well. Some people dont study like crazy for the step2ck but still do great on step 2ck because those people really learned their stuff well during 3rd so a lot of it is still in their memory. It is probably easier to do well on step 2ck than step 1.
However, it is certainly possible to get a lower step 2ck score than whatever your step 1 score was. How much that would effect a residency application considering that the step 2ck is lower but still respectable, is up for debate. It is probably true it will not have much of a negative impact on residency unless the drop from step 1 to step 2ck is >25-30 points. Even then, if someone's step 1 score 265, then would you consider a 25 drop to a step 2ck score of 240 a bad score? Obviously not. Both scores are great.
Most people agree that step 1 score is more important than step 2ck score unless the step 1 score is low. In that case, a high step 2ck score might become a little more important.
These are all generalizations but I would say that the bottom line is that if a person did well on the step 1, it is very unlikely that such a person would fail the step 2ck.
