Do they clean the machine? Yes.
Are the capsules of good quality so that after 3-4 consecutive cleaning cycles where the machine heats up, they don't become mushy and melt, sticking to the coffee machine? No. They are not quality. So if you overdo it even a little, good luck with the cleanup.

So far, I have only used it once but it cleaned my coffee machine perfectly. I used a descaling capsule and liquid to clean the water tank, and now it's like new. I ran the machine several times after using the capsule to ensure that no cleaning residue remained, and I didn't feel any residue in the taste of the coffee after cleaning.