Client : We want to develop this particular software. While developing it, we will be following Agile methodology.

Developers: Sure.

After developer achieves few features and decides to give 1st Demo of the software to the client.

Client : Wtf is this? This is an incomplete software, there are bugs in it.

Developer : Yes, you point that out to me and I will solve them.

Client: What do you mean point them out for you l, couldn't you do it yourself?

Developer: As a standard method, we often do unit tests, but we are not testers and with a strict deadline to match, we are more on the core implementation then checking again and again for minor bugs.

Client : I thought it would be a full proof software without any bugs in the 1st demo.

Developer : Software development is a process. It's not straightforward, hence you only mentioned at the initial, it's agile.

Client : If that's so, let's make it not agile and make you rot in hell for the next few fays. Now you next time show me a demo with no bugs, great complicated features and we will not mention you our expectations, predict them by yourselves, and most importantly, here's an impractical strict deadline.