Reasons:
Do’s of a tester:
Finding bugs in the software
Finding the bugs correctly and in the less time
Make sure that all bugs can be fixed as early as possible.
Don’ts of a tester:
Don't post the bad news to the developing team earlier
Make sure to double check even though you can't find if you can inform them.
Act like a professional to other team members
Control your enthusiasm if you are a tester
Reasons:
We can say that it is a disciplined activity because it goes through step by step procedure
If we miss one step we may get the test errors
We can say it is a technical profession because we are using
sophisticated tools
advanced technologies
rewarding career growth
if software is simple and more manageable software testers are untrained,we can't find bugs in the software
If we put millions of money on the team we couldn't get a single test error in it.