The main reason in introducing automated tests is time. As a
tester you need more and more time to verify the new components
in the application, so as the application grows bigger retesting
the old modules is very time consuming and can become boring thus
human errors are introduced.
One solution to this problem can be hiring more testers but for
a big testing team you need to make more efforts in managing it
this means more money involved. We already have three big problems
here: money, time, and quality and here comes the solution provided
by automated testing.
The main purposes of automation are to reduce testing time by
verifying the areas that have been already tested while maintaining
the same level of quality. In this way we avoid spending more
money time and efforts in hiring more testers because those new
testers need an adaptation period, training and logistisc expenses.
You will say here that automation tools are very expensive, an
automation expert costs too so what should you do? It is true
on short term an automation solution is more expensive than hiring
a few new testers but think a little in the future... as your
new releases are developed you will need a few more each time
and on longterm the expenses will grow bigger. Thinking on longterm
an automated testing solution is more advatageous. The initial
investment is bigger in case of automated tests but it pays back
in time because it gives more time to testers to perform ad-hoc
testing which can reveal many issues. Another reason would be
regression testing, the more releases you have, more regression
tests you have to perform and this is time consuming. Imagine
how comfortable would be to know that your regression can be performed
in half or a third of the time it would take to perform it manually.
Nowdays all software applications are used by numerous users so
performance tests must be conducted, in this case you must have
an automated testing solution implemented.
In case you choose to implement an automated solution make sure
you have at least one expert on your side otherwise the expensive
testing tools you have bought will end up forgotten on a shelf.
In conclusion if you want a performant and well tested software
in a decent amount of time you should consider implementing an
atutomated testing solution, but do not think that it will replace
your manual testing team.