The Ethiopian Captain thought they were entering a stall and wanted to gain altitude. Conditions in Egypt at the time made gaining altitude more important than at other airports.
The crew desperately tried to gain altitude and fought the computer (MCAS) that kept nosing the plane down because the angle of attack (AOA) sensor was broken on takeoff.
Boeing did not use redundant sensors for input into the MCAS system like Airbus does for its many automated systems.
Typically, you use at least three sensors so you can have two that agree. Airbus does that....but they have experience in computer-controlled flight.
Boeing does not and messed this up big time.
“The Ethiopian Captain thought they were entering a stall and wanted to gain altitude.”
WRONG! They were pulling back on the yokes trying to establish attitude.