If you use the command "/effect give @p minecraft:levitation 10 255", and if you are in the air,
after the effect ended you fall you (that is right so far...).
But if you then touch the ground, you bounce up and killed.
( I don't know if this is important, but I want to tell you this )
EDIT: If you are lower than ten blocks in the air, you not will death. Then you only bounce up (ok, you lost lives...)!
And sorry for my bad english...