Seeing this when you're 3/4 through finishing your project:
|Awww sh!%, come on, just 4 more seams!!|
Or your rotary cutter jumping the ruler and taking a slice out of your finger.
|It stopped bleeding...eventually|
Or your seam ripper going rogue while opening a buttonhole and ripping halfway across the bodice 3 days before you have to stand up in a wedding. (Someday, Vogue 2960, someday.)
And that's not even delving into picking out stitches gone awry (sonofab!&@$), machine needles breaking and rocketing around the room (f*@$), fabric doing a slip n' slide under the presser foot (g^dd#mm!t), or the many other hitches and stitches that throw a project (and your clean language) off the rails.
I need more coffee.