When buying anything, we first look at whether the thing we are buying does everything that we are looking for it to do.

Next, we look at whether it does anything that we don't want it to do.

Finally, we look at whether it costs less than the value we ascribe to it.

Anything else that it does or doesn't do is immaterial to us.

Advertising messages and salesmen try to mix in messages about these other things and make us feel like our purchase decision ought to be influenced by them.

And we fall for it sometimes.

When we feel like we aren't sure and that we're on the receiving end of a sales push, we will do well to step back and look at the three things that matter.

Those are the only things that matter.