Because he's a psychic or "magical" Pokemon part of a 3 part thing. The lowest form being Abra, then Kadabra, then Alakazam. Like some magician say when they are doing magic tricks. Abra Kadabra Alakazam!
Alakazam
Alakazam does not evolve
Abra, Kadabra and Alakazam are all based on traditional magician's phrases, Abra-kadabra, alakazam. These Pokemon are psychic Pokemon, so it fits.
First You need an Abra Evolved into Kadabra. Then You need to Trade Kadabra to a person where it will evolve to Alakazam. Then that person MUST trade Alakazam back for you to have Alakazam in Pokedex.
Alakazam doesn't evolve.
kadabra evolves into alakazam when he is traded.
Trade Kadabra to get Alakazam, and Haunter to get Gengar.
Kadabra evolved into Alakazam when it was traded.
Abra only evolves twice: into Kadabra and Alakazam. Alakazam does not evolve, as it is the final form of Abra.
Alakazam. Wait, what team?
The duration of Alakazam the Great is 1.47 hours.
My Kadabra can't so I doubt that Alakazam can.