What a data recovery lab claims ..
Let’s look at the claim that Seagate makes for it’s data recovery services:
Source: https://www.seagate.com/www-content/product-content/ironwolf/files/ironwolfpro-ds1914-5a-1707us.pdf, I took above screenshot at May 2021. 90% success rate, I call that pretty impressive.
And what a data recovery lab actually recovers ..
Then I read this interview with the manager of Seagate Data Recovery Services in Amsterdam, they’re right next to Schiphol airport. I took screenshot from the article in May 2021: https://www.dutchcowboys.nl/technology/onherstelbare-data-wordt-hersteld-in-aalsmeer
Google translation of above text (a bit clumsy):
“We simply do not start 20% of what we receive, because we can already visually determine that the data on the disks has been irretrievably lost,” says Melvin Plak. “From the remaining 80% we can still achieve a success rate of 90 % submit”
Are two different things ..
So, paraphrasing, they dismiss 20% immediately. Then of the remaining 80% they successfully recover 90%. So from each 100 drives they successfully recover 72. Then it seems to me the success rate is 72%.
Now it may look like I am trying to make look Seagate bad, but I suspect many labs are this creative with their numbers. This just happens to be an example I stumbled onto. And FWIW I don’t see the need for these flattered claims as I think a 72% success rate is still quite impressive!
I think you should take all numbers that data recovery labs claim with a grain of salt.