It seems to me that “evaluating the product” and “discovering problems that threaten the value of the product” would be worthy additions.
I’m also curious about “fixing things”. Lots of people fix things, of course—lots of things are broken, after all. Yet it seems to me that when we’re fixing things (in the product) or “improving software” we are not doing testing work, however valuable it might be to fix or improve stuff.
I make this point because there’s a difference between what software testing is and what somebody called “software tester” might do. The other stuff—the stuff that doesn’t involve learning about the product and the context of its use—interrupts the testing work; learning about the product by exploring and experimenting with it, with a special focus on finding problems. Interrupting the testing work with other stuff is fine, too, as long as nobody harbours any illusions that the product is being tested while the tester is fixing things.
To give a parallel: a researcher might be a lecturer from time to time. But when a researcher is in the middle of delivering lectures, it’s important to note that research work isn’t getting done. It’s not a bad thing to do lectures! It’s good for researchers to do lectures! But let’s remember that when a researcher is standing in front of an audience delivering a talk, no research is happening. And that’s fine too, as long as nobody harbours any illusions that lab work is being done while the researcher is on tour.