It happens....you're deep into your work and then...you see it...a mistake. You instantly ask yourself why didn't that pesky little error show itself 10 rows ago. You review the remedies...1) leave it and pretend it doesn't exist (who cares if others can see it...it makes the piece unique) or 2) make a note to return later where "X marks the spot" and correct it in a way that no one else would ever know it marred your work of art; or....3) rip it back to the point of error and start over (frog it or tink it).
Funny terms, frog and tink. If you didn't know, ripping back refers to the ripping, as in the sound a frog makes...thus, frogging. Tink, however, refers to ripping back when knitting.... K N I T backwards....T I N K. That last little gem was told to me by Barbara G and I'm glad she shared it with me.
So, basically, we all make mistakes in our crocheting and knitting on occasion. The decision to leave it, revisit and correct it, or rip it back pretty much depends on the item itself and whether or not you insist on perfection. Personally, if it is a gift, I feel it is necessary to rip it back or "seamlessly" "invisibly" repair it as if it never existed. On the other hand, if it is for your own use, or something for "around the house" or a utilitarian item such as a dishcloth....you may want to leave the error be...especially if the mistake isn't terribly obvious. We are are own worst critics...perhaps tho, someone else would be hard pressed to find the mistake.
So, these are the considerations and options whenever this happens. Ultimately, the decision is yours.