That a human agrees that the product works correctly. These can be silly things like observing that buttons overlap, or observing misspellings.
"What is it that you're testing manually that you can't automate?" I can't automate what I can't predict.
Simple example: Would you get in a robotic car that only had automated testing? What about a robotic flying car?
Real example: 20 years ago, I bought a modem that had an "obvious" problem when calling a dial-up BBS. It didn't flush the buffer appropriately, leaving me with an incomplete screen of text.
I'm sure the modem passed all of their automated tests! But, did whoever wrote the automated tests predict that the buffer should flush if no data came within a very small amount of time? Nope!
Another example: Have you recently used Netflix on Android with Chromecast? It breaks in a lot of corner cases when you put your phone in your pocket. Netflix proudly laid off their manual testers and only does automated testing. Can you really automate every aspect of the Chromecast in a test harness? I bet you can come close, but not achieve 100%.
"What is it that you're testing manually that you can't automate?" I can't automate what I can't predict.
Simple example: Would you get in a robotic car that only had automated testing? What about a robotic flying car?
Real example: 20 years ago, I bought a modem that had an "obvious" problem when calling a dial-up BBS. It didn't flush the buffer appropriately, leaving me with an incomplete screen of text.
I'm sure the modem passed all of their automated tests! But, did whoever wrote the automated tests predict that the buffer should flush if no data came within a very small amount of time? Nope!
Another example: Have you recently used Netflix on Android with Chromecast? It breaks in a lot of corner cases when you put your phone in your pocket. Netflix proudly laid off their manual testers and only does automated testing. Can you really automate every aspect of the Chromecast in a test harness? I bet you can come close, but not achieve 100%.