It’s amazing how this rule never seems to apply to the other half’s shoes, handbags etc and it would be a very brave man who dares to mention the cost or frequency of the Hairdresser!
The inside as shown is the static side of the calliper I.e. only the outside has the piston that moves. The inside is adjusted by an Allen key so the pad just doesn’t touch the disc. The outside needs a special magura adapter to bleed the brakes.