1. Designer color decision

The designer mostly selects colors using the following:

• color selected on the monitor display
• a physically printed sample from a fan book or past prints

This is very often inaccurate - the huge  error might be affected by the following:

• non-perfect printing (fan book, samples from the past)
• aging of a sample
• different substrate/raw material used for color sample
• non-D50 lighting condition when judged
• the difference in surface (matt, gloss, textured)
• potential partial color blindness (8% males and 0.5% females worldwide)
• sample not rendered accurately on display (non-calibrated profiled monitor or/and out-of-gamut sample)
• no controlled lighting condition for critical color decision 
• changes in colorants (some of them are subject to restriction due to pollution and are not available anymore - new replacements are not identical)
• wrong settings of color management of design software
• lack of knowledge about colors