Investors are still waiting for this eVTOL stock to take off.Joby Aviation (JOBY -2.35%), a developer of electric vertical takeoff and landing (eVTOL) aircraft, probably hasn't minted any new millionaires since its public debut. Its stock opened at $10.62 after it went public by merging with a special purpose acquisition company (SPAC) nearly four years ago, but it only trades at about $11 as of this writing.Joby's stock didn't take off because it barely generated any revenue, it was racking up steep losses ...