[tdubhro1]

I think for many people “Bug” can imply something that crawled in from outside and messed up the system, “defect” implies that there was an avoidable deficiency in the specification or the implementation. The engineering mindset might prefer “defect” since it implies that we can fix the process and improve the quality of future products, whereas “bug” implies these things are just a fact of life and you can’t expect to eliminate them

[ryandrake]

I’ve started using “defect” instead of bug for these reasons. The “bug” euphemism implies the software was once correct, but then problems crawled in from somewhere external to infest the otherwise good software.

That’s really not how 99% of software problems happen. They are defects because the software was defective from the moment it was conceptualized or typed in.

“Bug” tries to soften/downplay the developer’s role in producing a defective program.