Many customers request data sheets when they order samples. This is a good source of information to get a good idea of the tape's characteristics such as thickness, adhesion, elongation, tensile strength, and color. For some tapes, the data sheet also documents operating temperature range, dielectric strength, tack, or shear strength.
While this is good information to have when comparing tapes "by the numbers," it won't always tell you what you really need to know – will this tape work in my application.
The only way to know if a tape will perform at the level you need in your application is to test it in real world conditions. Adhesion is a great example. The adhesion level shown on the data sheet is based on the adhesion the tape has to a clean, stainless steel panel. If you are applying the tape to any other surface – a box, a wall, a polybag – the adhesion level almost certainly will be different.
When tapes are tested, it is done in laboratory conditions. The temperature, the humidity, and the cleanliness are controlled. You probably don't get to control those variables in your real-world situation. So, when specifying a tape for a new application compare the data sheets first. But always get a sample and do your own testing to make sure the Tapeworks.
Use data sheets to get the numbers, but real-world testing is the only way to prove how a tape will perform in your application.