What are the tradeoffs of allowing students to submit test corrections? Do you allow students to submit "test corrections"?  Meaning, do you allow them to take the questions they missed on a test, denote the correct answer in some way, and give them partial or full credit back if they then get the answer right?

If so, why?  If not, why not?

I'm wondering, because I have a colleague who has ALWAYS allowed test corrections in her CS courses for half credit.  I NEVER have.  But this year, for some reason, I am getting a lot of lip from students like "What! No test corrections?!  But Ms. Xxx always let us do test corrections!"

I believe allowing test corrections (which is essentially a retake) does a disservice to the student because it allows them to be lazy.  They don't do it right the first time. They don't study (or don't study as much as they should have) and depend upon "corrections" to make up for their laziness.

My colleague believes allowing test corrections at least forces the student to "discover" correct answers to questions they may have never revisited otherwise, and that therefore they have another opportunity to learn.

Am I being too hard?  What do you think?
Our district has a policy that any student that scores under a 70% must be allowed to retest. You take the retest score, average it with the original, and cap it at 70%.

Catch is that I teach all AP / Honors classes. Typically these aren't students that score a 60% and want to bring their grade up to passing. They're the kind of student that gets 88% and is unhappy they didn't score an A. 

I go beyond that and let anyone who wants to do test corrections instead of a retest and they'll get half their points back. We have another AP teacher that does a square root curve if they turn in corrections. 

To get credit they turn in a document with a screenshot of the question (tests are all in Canvas), explain why they picked the answer they did (sometimes "I guessed" is okay), what the right answer is, and most importantly why it's the right answer. 

3 reasons why I do corrections.

1 - It lets me throw a few harder questions into a test. I start putting in AP style questions early in the year, which students may not be used to. As the year progresses more and more AP style questions get put in. If the longer questions go in, especially early in the year, the tests might be a little too difficult.

2 - I don't really care what they know Tuesday at 10:30. I care what they know when they leave my class at the end of the year. If they can come back after a test and prove they know the material, that's much better than just leaving it unknown.

3 - Everybody has a bad day. Maybe their dog died last night and they're not in a good mindset to take a test. 

With all that though, I'd rather do retests. Still for half credit. The problem I'm facing with that is I'd essentially need at least one more full test for every unit. Otherwise they're retaking the same test. What I'd really like is to have enough questions banked that students could take a retest 2 or 3 times and I'd average everything together. But that would take hundreds of questions for each unit.