Pros and cons of free tests

“An issue comprising two key points, namely a) why do tests and b) should they be paid for? Plus a third, subsidiary point which irritates yours truly beyond all reasonable measure, so we’ll come to that last.
So, a) “why do tests?”
I confess, I think “why do tests” is probably a little simplistic – it should be “what need drives clients to ask for tests and do tests meet that need?” – but I was looking for a short sub-heading.
Three reasons justifying requests for tests
The obvious first point is that clients ask for tests in order to test (naturally enough) that translators can deliver what they say can deliver. If you claim to be a legal translator, that you can translate a paragraph or two from a contract. If you claim engineering knowledge, that you can translate the description of a cable stay for a bridge, say. And so on. Unfortunately, the translation business is full of people with a misplaced confidence in their abilities, or who deliberately mislead clients, and anything in between. Your exams and credentials may be perceived as not having examined the specific subject area to the depth that a client may need. Or maybe the information about you in the public domain doesn’t really indicate much one way or the other. So they ask for a quick couple of paragraphs to prove capability to deliver.
The second point is that clients may ask for a test to check translators can follow simple instructions. I have limited outsourcing experience, and even I can tell you that some translators will get the document, and just jump into translating that document, before they have read the accompanying email all the way down to the inevitable “Regards….” bit. So asking people to start at the third paragraph (say), can just be used to test how much attention the translator pays.
Third, they may ask for test to see if you are actually able to meet technical or ancillary requirements. Can you handle XML? Provide a TM in TMX format for the client? Giving the translator a handful of HTML pages and receiving a nice Word document back, even if translated perfectly, may not be what is required.
Counter-arguments – valid
A common counter-argument to that first point is that samples demonstrate the same thing. True to an extent, and more so for a specialist. As a counter-counter-argument, I would say that I would expect a sample made available to be as near to perfect as a translation ever gets, and all it demonstrates is the ability to hone that particular text to the nth degree. It does not necessarily demonstrate the ability to deliver the specific type of text the client requires. And it in no way demonstrates the important additional ability to follow instructions. And neither do credentials, certificates, diplomas, membership of professional organisations, or indeed paid membership of popular translation websites. Some of these can indeed be easily forged, faked or presented in a misleading way, and also be a bit of a bugger to check, particularly from another country.
A more reasonable but conversely less universally-applicable counter-argument is that if you are being asked for a test, you probably don’t know the potential client from Adam, and the potential client also does not know you from any other character from the religious text of your choice. So we should be careful. It is certainly safer to acquire new clients by personal recommendation and referral, and the same is partly true of agencies using new translators. I have also heard the viewpoint that a client who is testing several people (not that we usually know how many are being tested at once) is likely to view each of them as interchangeable or disposable, initially at least, until they prove otherwise. Once again, a spot of (demonstrable) specialisation is your friend.”  Source: proz.com