What does "Je n'arrivais pas a bien fonctionner les taches." mean?

In Ukranian, it translates to this:
Я не міг добре працювати на місцях”.
“YA ne mih dobre pratsyuvaty na mistsyakh”.

In English,

“I couldn’t work on the spots well.”

Google is your friend.

@elbanditoroso Ok, but that doesn’t go with the context that I have so there must be another meaning to it. Something to do with tasks. Thanks.

…Forget that post, working on the spots is a task.

It looks like “tache” can also mean a spot, like a a spot on television or in advertising. Could that definition fit better in your context? “I wasn’t able to make the spot work well?”

It’s french. I couldn’t work on the spots. Was it the rug cleaner guy? Or I couldn’t work on the tasks. . Really depends. “Je n’arrivais ( I couldn’t ) pas a bien fonctionner (work well) Not work well, les taches (spot or task). Fonctionner actually means function but it depends on the sentence structure.

How about self assesment at the work place?