Compare the line, not only the label
Look at the thread thickness, twist, sheen and stated length for the exact product. A brand name covers several ranges, so two colour cards from the same maker can still behave differently.
Wind a short sample through your fingers and stitch a few rows. Notice whether the thread settles into the cloth or feels too dense for the holes and weave.
Plan colour and quantity together
Choose a colour family before buying individual shades. This makes it easier to keep a project coherent when you need a second skein or want to add a border later.
Check the length as well as the price. A lower price per skein may not be lower per metre, and a colour that is difficult to replace can be inconvenient for a large cloth.
Use one range consistently
Mixing brands can work, but do a swatch when adjacent rows need to look uniform. Differences in twist and surface reflection can show even when the printed colour names appear close.
For a first project, choose the range with the clearest colour information and the thread weight that feels comfortable in your chosen needle. Confidence while stitching matters more than brand loyalty.