Requirements sometimes are like pilars...

If requirements meet the ISO norms, the laws and rules, then the software program wil survive, your project will survive and/or the company will survive. Whatever is at hand. 
The pilars are important. But in software testing manytimes the requirements are interdependent. They are related to eachother.
I've thought about a schematic respresentation.
This is what I've came up with:

In this example it's clear to see that the most upper pilars are the strongest.
But wait. That's probably not the way you'd like to build your software, right?
So, where do you start testing?

Exactly at the foundation, at the base. So you need to think hard on what the most important requirements are. 

Many times I see people work hard, but they are not focused on the most important things. Selling a product 999x is nice, but would you like to sell a product which is wobbly and doesn't meet the requirements?, of course not!

Well, with this in mind you might want to read the great Twitter post of  a highly appreciated expert in the field :
https://twitter.com/michaelbolton/status/1123664036418211840

In essence: of course you want to test the most important requirements, the lowest pilars hypothetical spoken in this case. But in order to be sure all the base requirements are tested well... you must have a sharp eye on a couple of important things.
Remember in software testing,
​paradoxes always lurk!

Many times during software testing you stubmle upon difficulties. One of them is this:
​

Recently I read a very interesting message on Twitter about software testing. In it, was a picture of how you should look at software testing and how formal or informal the tests could be executed.

But when I see such pictures, sometimes I inherently think:

'Am I the only one who thinks this is a bit "shortsighted?"
This is not the complete picture. This is only a certain % of the total view of how it should be looked at.'

#1: One of the most important things to understand is: that this overview is very dynamic. It's not a solid state. 
So keep in mind you should see the picture more like this:

#2: is that: you're not testing just 1 requirement or functionality of the software.

It's important realize that requirements are connected.

It's important to realize that: requirements have hierarchical connections. Some have high priority, some have low priority. Some are connected to a small amount of others, some are connected to everything.
But they are all connected to eachother in some way.

So this is more in line with how you should see it in overall.

Example: You're testing software: It has requirements. You start with play and test the most important requirement there is. Then you start to machine check the damn thing. You discover a bug. A new requirement is written, that requirement becomes the new top priority. Could be connected to almost nothing, could be the new most important requirement...

#3: Realize that more formal or more informal testing is something very dynamic regarding to the test object!

Realize that, now we've underlined that fact. That we have left out all other aspects that determine how you should test.

So for example: is a requirement more 'security testing' related?
or
is it more 'performance testing' related?

None of that is yet mentioned in my extension (personal view) on the image 'formal - informal'.

#4: I'm not even mentioning the fact that insights in time regarding a requirement many times change... (what looks like a bug becomes a feature) (which makes it (the pyramid of connections, and how to test it) even more complicated)

In essence!!:

....
Somtimes you need to adjust the strategy of the project. (for example: more A.I.)(or, add other types of software testers for example testers with knowledge of A.I.)

Sometimes you need to adjust the strategy of the tets object.

Sometimes you need to adjust the strategy on some requirements (or bugs, I will get back to that later (in English)!).

Sometimes you need to adjust the strategy on 1 single requirement. (Realize that testing 1 requirement can cause a change of strategy for the.... [ (project, test object, etc...yes it's that complicated! ) ] 

and so forth, and so on....

So if you have a picture in your head of a test object (software code) that matches something that is static!?

It is NOT! 

A testobject is something very DYNAMIC!

(so in the future, when your "manager" asks: 'why is testing taking so long?' you show him this picture and say: 'because THIS! is what we are testing!'):

Ohw by the way, once you see a test object as something very dynamic, it also is immediately clear why it can be so difficult (time consuming) to automate everything, right?

So don't look at software testing which looks something like this:

DO look at software testing which remsembles something that looks more like this!:

When I see the applications for software testers nowadays ("doctor needed!"). And I look at what the companies are asking for the kind of skills a software tester should have. I'm sorry to say but it is not in line with what I would like to see in a software tester. Not even for 60%...

(So if you would like to scout for the real good software testers in the field, and you'd like to hear my vision about what a real software tester should have in the backpack as skills?

Send me a message and I gladly tell you all about it!)

or,
You'd like your recruuters to just have a cup of coffee (a talk) with me!? I can elucidate my vision regarding software testers and help them find the more suitable persons for the concerning applications more easily (faster and better).

Yours sincerely,
Ing. Valentijn Peters