Testing and quality
Quality is conformance to requirements, not 'goodness' or 'elegance'
usually attributed to Phil Crosby
Testing is measure taken in order to make sure you get exactly what you expect. Or very much like it. Or has some of expected features. At least. Testing deals with how you put your expectations into words and as such is closely connected with message-sent-is-not-the-same-as-message-received thing. This is where requirements come in and analyst plays his/her part.
Ok. Suppose we agreed on meaning of words and shared goals, how do we prove we got what we wanted? And this is where testing starts and test specialist appears on the scene. In an everyday common context test stands for "checking". In a narrower scientific context it implies a number of actions that prove some statement. Do you remember functional logic? If something in a statement contradicts actual reality or common sense then statement is considered to be false. Otherwise it is said to be true. It works pretty similarly with the testing except that reality and quite often common sense are replaced with requirements. If test results contradict requirements then test is failed. If test result are in perfect harmony with those requirements then test is passed or, in other words, we got what we wanted (or agreed to think that we wanted this).
NB: Sometimes results turn out ot be false positive or false negative. This may happen due to a number of reasons like poor understanding of what is going on, ambiguos requirement or something being wrong with the test design. We are dicussing this a bit later.
Roughly all tests may be split into two categories: tests that try to confirm that anything works alright and tests that try to prove there is something wrong. Scientifically these two approaches are called verification and falsification and their history goes as far back as Karl Popper's writings and even further then that. It is important to remember that this in no way contradicts or replaces specifict methods of building test coverage such as equivalence partitioning, boundary values analysis, cause and effect, error guessing or exhastive testing.[1]
Why mess with science when the only thing we want is to make sure it works during sales demo? In fact this question is crucial and the answer is simple. If your goal is just to sell something that somewhat works then testing is not necessary. Testing is only required if you expect to get something specific and getting what you expect constitues quality. In case you need quality messing with science is unavoidable.
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Footnotes:
[1] Based on this page (Russian with automatic traslator): About testing
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To be continued in part 2
Quality is conformance to requirements, not 'goodness' or 'elegance'
usually attributed to Phil Crosby
Testing is measure taken in order to make sure you get exactly what you expect. Or very much like it. Or has some of expected features. At least. Testing deals with how you put your expectations into words and as such is closely connected with message-sent-is-not-the-same-as-message-received thing. This is where requirements come in and analyst plays his/her part.
Ok. Suppose we agreed on meaning of words and shared goals, how do we prove we got what we wanted? And this is where testing starts and test specialist appears on the scene. In an everyday common context test stands for "checking". In a narrower scientific context it implies a number of actions that prove some statement. Do you remember functional logic? If something in a statement contradicts actual reality or common sense then statement is considered to be false. Otherwise it is said to be true. It works pretty similarly with the testing except that reality and quite often common sense are replaced with requirements. If test results contradict requirements then test is failed. If test result are in perfect harmony with those requirements then test is passed or, in other words, we got what we wanted (or agreed to think that we wanted this).
NB: Sometimes results turn out ot be false positive or false negative. This may happen due to a number of reasons like poor understanding of what is going on, ambiguos requirement or something being wrong with the test design. We are dicussing this a bit later.
Roughly all tests may be split into two categories: tests that try to confirm that anything works alright and tests that try to prove there is something wrong. Scientifically these two approaches are called verification and falsification and their history goes as far back as Karl Popper's writings and even further then that. It is important to remember that this in no way contradicts or replaces specifict methods of building test coverage such as equivalence partitioning, boundary values analysis, cause and effect, error guessing or exhastive testing.[1]
Why mess with science when the only thing we want is to make sure it works during sales demo? In fact this question is crucial and the answer is simple. If your goal is just to sell something that somewhat works then testing is not necessary. Testing is only required if you expect to get something specific and getting what you expect constitues quality. In case you need quality messing with science is unavoidable.
-------------
Footnotes:
[1] Based on this page (Russian with automatic traslator): About testing
-------------
To be continued in part 2
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