Epson K3 ink expire date..

As an illustrator who has worked with oils, acrylics and inks I don't get the so-called 'expire' date of Epson K3 inks.. I believe Epson says it expires after 6 months of installation. Really? Well, then what exactly will happen after this six months period? What is going to be the problem? Will it fall out of suspension? Then just a shake will correct this. For the rest I cannot figure out what components in this ink will 'expire'. I have so many paint stuff in my studio that simply survives for years if kept away from heat or oxygen. After a good search on the web I find this questions from others users as well, but no stories of degraded print quality when inks are used (far) beyond their expiry date. Who has used inks beyond their date and has had problems, like degraded ink color quality or clogging? Or a bad hair day?