This question:
Question about Spells with Thunder/Lighting
was closed by @SevenSidedDie and others for being too broad.
This question has 5 votes and is open:
Question about Spells with Concentration.
I edited my question to be almost the same as the other, but that still didn't change the evaluation.
Concentration and Thunder/Lighting damage are just attributes of 5e spells, I fail to see a difference between the two that would explain the different treatment they get here.
In comments, @SevenSidedDie refused (as is his right, of course) to tell me the difference between the two, as in why one should stay open while the other one should be closed. Maybe someone else can explain this to me?