When you talk about knit strength / crochet strength you mean the number of stitches and turns per centimeter.
A lot of carelessness is to do a test tag. You simply knit / crochet a small piece of paper to see if you have the same masking strength that is in the pattern you should do. If the mesh strength is not correct, the end result will be affected. Different things that can affect mesh strength are your own style, if you knit / crochet hard or loose, how thick the yarn is and what size you have chosen on knitting / crochet needle.
On the yarn banner you can usually see something like 10 x 10 cm = 21 mx 30 v with piece 4. This means that on a plain knit square that is 10 x 10 cm, there will be 21 stitches and 30 turns if you knit with 4 stitches. If your mesh and lap numbers match those numbers then it will be right. If it does not, then change the size of the sticks in the first place. If you knit too loose you take smaller size, if you knit hard you go up in size.
Remember to mask off before you measure, and preferably knit a few turns / stitches extra, then it will be easier to measure and read correctly.