One of the very gratifying things about knitting is that a lot of mistakes are relatively easily fixable. Take these socks:
This is the first pair of socks I knit for my dad, last Christmas. And it turned out that they didn't fit. Not where you'd expect- they weren't too long or too short, too tight or too loose. No, the heels were too pointy. The rest of my family is rather unusual in that we have very nearly all the same size feet. And I've gotten used to slipping in a few extra stitches in tight patterns to add ease over the arch, and making the heel deeper. My dad, however, apparently has broad heels and low arches. When he tried the socks on, they stuck out at the back in like elfin-shoes. (At first I used the phrase 'round heels' when discussing it with my parents- my dad objected vigorously to this.)
So, for any future socks, I clearly need to turn the heel early, making the whole heel a bit shallower and wider. In the meantime- I needed to fix these socks. These were knit toe-up, using a short-row heel, so changing the profile of the heel was actually rather easy. We pinned the sock to mark the excess fabric, and then I snipped a strand of yarn at that point on the leg side of the heel. (In the middle of the row, on the second sock, after I realized on the first one that I needed some slack for weaving in loose ends.) Then I unraveled the row across, put it on a needle, and ripped the heel back through the turn until I reached the equivalent row (to the starting point) on the bottom of the heel. Neatly enough, I wound up with the same number of stitches on the sole side, picked those up on a second needle, and then just grafted the two sets of stitches together. Absent a few short bad words when I pulled the thread through in the wrong direction and made holes instead of seams, and weaving the ends- that was all there was to it.
I can't say I'm overly fond of actually doing kitchener stitch, but it's a darned useful technique in a pinch. And way, way better than reknitting half of each sock!