Contentment vs. Complacency

contentment-

–noun

1. the state of being contented; satisfaction; ease of mind.

2. Archaic . the act of making contentedly satisfied.
http://dictionary.reference.com/browse/contentment

complacency-

–noun, plural -cies.

1. a feeling of quiet pleasure or security, often while unaware of some potential danger, defect, or the like; self-satisfaction or smug satisfaction with an existing situation, condition, etc.

2. Archaic .

a. friendly civility; inclination to please; complaisance.

b. a civil act.
http://dictionary.reference.com/browse/complacency

Is it just me or is there a thin line between contentment and complacency? In anything, especially in my line of work, there is no room for complacency. Ideally, I'd close a deal and then move on to the next. There's not supposed to be any room to be complacent.

The thing is, I think it's my nature to just sit still sometimes. I am not really the intense type of person to just keep going and going and going. I think it doesn't take much for me to be contented.

Like every time, I don't have a point to show. It's just that it's difficult for me to push myself hard after I close a huge deal and I can't really pinpoint if it's complacency or contentment that I'm feeling.

Oh well, I dunno. I'll figure it out eventually.