人无完心
[rén wú wán xīn]
Loosely based on a common idiom “人无完人” (ren wu wan ren) - which means 'no man is perfect' or 'everybody makes mistakes', the phrase replaces 人 (people) with 心 (heart/mind), conveying an altered meaning possibly indicating incomplete sincerity, dishonest intentions, or a mind that doesn't fully commit to its thoughts and promises.