Typing them into the computer you get so many more opportunities to misspell them creatively, but that's not the real problem.
I work in a NICU, and NICUs have twins. The patients all have the same first name. Baby. The middle name sometimes changes - some have the middle name Girl, some have the middle name Boy. Occasionally we have one with no middle name, but that's a subject for a different day.
Twins are also supposed to get a letter after their name. A for the firstborn, B for the second. We keep going for the higher order multiples, but so far, triplets and quads have all had short last names, so it hasn't been a problem. The letter comes at the end: Lastname, Baby Girl A or Lastname, Baby Boy B.
The problem is our lab label printer. It only gives you so many characters. We've had twins with long names before, but the parents have usually been considerate and had one boy and one girl, so the labels come out different even without the A or B.
No such luck this time. Identical twin boys. Lab labels both appeared: Longlastname, Baby Boy - no letter. Same birth date too, wouldn't you know. We've had twins born on different days, but not these. They HAD to be born on the same day.
So labs were sent and we get a phone call from the lab:
VERY snotty lab tech says, "Did you really want 2 (insert lab value here) for Baby Boy Longlastname?"
I wasn't assigned either baby, but I knew immediately what had happened.
"Did you look at the medical record numbers?" I asked, "because they aren't the same."
Silence for about 15 seconds.
Greatly chastised voice says "Oh, I guess the letters didn't print. I'll just go run those now."
Yes, someone should have taken a second to write A or B at the end, but snotty lab tech should have taken a few seconds to check MR #'s too.