Ambient temp. and cable spec are always my first questions. They dictate the ampacity table selection. Other factors (e.g. raceway, wiring method) become multipliers.
The use of the 90degC rated cable column should ONLY be used if the motor AND motor control equipment are rated for 90degC, which is not standard.
Above 100A, 110.14(C) allows for the cable ampacity selection column for 75degC rated cables.
At 40degC, using multi-conductor cable, and without a cause for any additional derating, I would size the cable for 3/C 350kcmil + #3AWG GND (.88 x 285A = 250.8A @ 75degC), which is greater than 180A x 1.25 = 225. Unfortunately, 250kcmil = .88 x 255 = 224.4A, not that the AHJ would catch that. It (0.6A) would also not be a cause for concern for me regarding fire prevention, unless the motor was an industrial motor than runs continuously (like a paper machine headbox fan pump). But to design 'by the book' ....
If it was only one calculation, and one table lookup, I'd be out of a job.