Bugfree application?

Will you promise to deliver a bug-free application?

My senior was saying this to me, hopefully by this week we can solve all the problems, and we'll get a PASS for next week UAT.
Well, I do not know what to respond.
Can I say, "I'll try my best"?
This is a very common answer, isn't it?
But how can I make a promise saying there won't be any bugs or problems during the UAT?
Even Microsoft's products are having bugs after they released and sold to thousands or millions of customers, that's why they came out with all these service packs, isn't it?
I dare not promise for a bug-free application. I just kept quiet and listen to my senior's plan. :p

I'm already trying to meet the deadline, the project period has been shorten, then many new requirements have been added, even until today. Well, I have a few more pending enhancements to be completed by the end of this week. Having to fix the errors, and to add the new features, there are three more days for me to go.

Although I might not be able to do the better for this project, there is something I need to cater for the future projects.
From the internal testing bug list, I realized that I've missed out something during my own testing. (Well, I didn't really have time for my own testing.)
I plan to make a checklist for my future projects, I need to fulfill the checklist before I release my application for others to test. Although I need to start another project before I complete this, I surely need to take at least half a day to make a draft checklist.
Completing the projects is important, learning from the mistakes is as important too.
Never learn from mistakes, no matter how many projects I have completed, I didn't learn a single thing. That's not good.

Keep going. Work happily and live happily. ^_^