I've seen a ridiculous amount of questions (quite alot fairly low-quality) like this, or this, where the OP installed Ubuntu or something and lost their data, by not noticing all the warnings about disks being wiped, or by selecting the wrong thing to install to.
Is there a good question that these could be linked to? Most of the answers say 'use this program that won't work/is expensive' - though this one is OK. I know that the data is likely pretty much gone anyway (particularly if the disk is wiped by before formatting), but answers of higher quality could help. If you have just had half you life's work wiped by accident, you do sort of want it back....