Your monitor degrades all the time every time I recalibrate I have to tweak some setting, normally one of the rgb colors. If you calibrate every 2 weeks (I have been looking at the links I provided and they say every 2 weeks so I will be doing that now) you will be bringing the monitor back to a known standard and if you use the same printer profiles you will get the same results time after time when printing.

Eggiwegs! I would like... to smash them!