You want to avoid saying that you had a job turn out poorly but did nothing to correct the situation. If you admit that a project did not turn out the way you expected, but you did nothing to fix it, the interviewer will see that you do not pay attention to detail or take pride in your work.

"Yes, unfortunately, I have messed up a job pretty bad. Luckily, my first project was doing a remodel on my kitchen, so it was not for a client. I was new at laying tile and watched videos on how to replace the kitchen counters and backsplash. The video made it look easy, and I figured it would be a simple project. I made the mistake of not leveling out the counter before placing the tiles, so they were uneven when I went to grout. I did not finish the project before realizing my mistake and tore out the tiles before grouting. I leveled the surface, replaced the tiles, and then grouted. The finished product turned out great, and I learned my lesson from that experience."