It is my personal opinion that you need to test your potential partners for any red flags that pose a high risk in the future, or to see how compatible you are with them in terms of personal preferences.

To do this properly I also believe you need to do a few things.

First you need to actively listen but be skeptical to both what you hear and what you see and what is done. If something seems off in your gut, you need to test that off-ness.

Second, you must not tell your potential love interest they are being tested for many reasons but the main one being, it gives them an easy way to lie and pass the test.

Third and most of all, when a potential mate you like passes a test, unless you have factual evidence in their words behaviour or body language, you must not test again. You must trust that they are being genuine and authentic.

Fourth: With each passing of a failed test you should slowly give more of your love positivity. And with each failing you should be assessing how big a red flag or risk this failed test creates for you in the future, by further testing and weighing out the pros and cons and cause and effects of what these failed tests bring and wether that is a deal breaker for you relationship wise, and or friendship wise, etc.

So why do we do this?

Well the reality is that sadly, people do lie or tend to show the best and mostly not full versions of themselves (sometimes sadly, not even remotely authentic)

And here is an example.

1: if you are someone like me who does not find clinginess attractive, you may do a Neediness test. Easiest way to do this, is after hanging out for a day, and you notice some clingy signs, take a break from communicating from them until they reach out to you or at least a couple days and watch how they respond. If they show signs of clinginess or neediness then that is one point towards not being a good fit for you.

More examples in the comments below.