Lock and key

I asked a key
who had found his lock:

  "How did you know?
  What did she say
  to convince you?"

He looked at me a while,
then told me:

  "It's wasn't so much
  what she said --
  as what she didn't:

  a seamless joining together;
  a lack of noise
  to proclaim ill-fitting;

  an absence of effort
  where before
  there had always been."