Pretty simple question, but I couldn't find the answer anywhere. Suppose I have a standard '5-pin'/5 recesses wall-socket and I check it with a voltage tester. How many recesses should show a voltage? My expectation was 3, however in my case only the bottom right recess showed a voltage.

Context: this is in an apartment I just moved to in the Netherlands. I tried connecting my electric stove and 3 out of 4 plates no longer worked. That caused my to grab a voltage tester to check the socket.