Miele CM6x10 Operating Instructions Manual page 15

For machines with stainless steel surfaces:

Do not use sticky notes, transparent adhesive tape, masking tape
or other types of adhesive on stainless steel surfaces. These
damage the surface, causing it to lose its dirt repellent protective
coating.
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The finish on stainless steel surfaces is susceptible to scratching.
Even magnets can cause scratching.
Warning and Safety instructions
15