The feed zone (next to the hopper) should be the coolest zone, so pellets enter the screw solid and create the friction needed to convey them. If this zone is too hot, material sticks together in the hopper throat and bridges.
The middle zones melt and homogenize the material, and the nozzle zone is usually set close to the target melt temperature. Always take the exact range from the material supplier's datasheet.
Signs of a wrong profile: fluctuating recovery time, fluctuating cushion, burn streaks or unmelted particles in the part.
This note is general guidance. For exact settings, the material datasheet and the machine maker's instructions are the reference.