IPA: /ˌɪn.dɪˈfɛk.tɪ.bəl/
KK: /ɪnˈdɛfɪktəbl/
This word describes something that is flawless or perfect, and cannot fail or decay over time.
The artist's work was considered indefectible, admired for its beauty and precision.
Indefectible is formed from "in-" (meaning not) and "defectibilis" (from Latin "deficere", meaning to fail or to lack). The word describes something that cannot fail or is incapable of defecting.
Think of 'not' ('in-') being able to 'fail' ('deficere') — that's why indefectible means something that cannot fail.