Does hair dye affect your hair?

yes it damages your hair.

after awhile of using it your hair will start to fall out if you use out dated hair dye. Or leave it on for longer than the recommended allowed minutes in the instructions.

If you use some stronger dyes especially the red hair dyes it can permanently affect your hair color even if you cut all your hair off and regrow it back. There will be patches of red you catch in the light(I should know I was a red head for three years). As long as you use a good conditioner/shampoo that is made for perm or treated colored hair and don't over due it with the product you will notice minimal loss.