There are various  tags prices at the market. If judging from human eyes seems no difference, however, in deployment, lots of things will be in different.

Below features will effect the tag quality, and surely the tag production cost.
1) Chips
Nowadays, alien,NXP, impinj all recognized as high quality chip suppliers.
However, still be other chip supplier with lower price to saturate the market.
To chasing the low cost, some company using these cheap chip to fake, and sold as Alien,NXP,or Impinj. During the application, difference of the capability can easily tell.

2) Antenna
Choose the most sensitive designed antenna for specific application is important.
Ordinary, bigger the size of tag antenna will be better.

3) Paper of tag
Dielectric constant of paper material will have certain effect on tags reading effort.
Lower the Dielectric constant of paper, will bring a little bit higher of tag price.

4) Glue of tag
Dielectric constant of glue will affect tag’s capability.
Choosing the glue with lower dielectric constant, will get better performance, but higher the cost.

5) Binding process of chip and antenna.
Bad binding machine will bring bigger defected rate than good one.
Expecting in big quantity, some of the machine could bring the defect of tag in big pat of the goods.

Hyintech could ensure you excellent quality and capability.