Why should you avoid parallax?

Answer 1

There is no such way to avoid parallax error, you just have to be careful.. :)

Answer 2

Always align yourself up with a fiducial mark, horizontally and vertiacally. This will minimise paralax but will not completely avoid it. Human error will always occur

Answer 3

People may wish to avoid parallax because it's a distortion. However, a parallax in a photograph doesn't always pose a problem.