It encourages/reminds you to keep your details current so they can provide a proportional and appropriate response to an activation. My PLB is recorded against my vehicle and thats where it normally lives, it will confuse the hell out of them and delay a response if I decide to take it out to sea and activate it from my kayak.
Usually in an activation a risk matrix is done on the information available and then some effort is made to contact the registered owner of the PLB or their next of kin to gain further basic details, they can't do that if you have changed your phone number or wife

. The last marine/boat drowning I was involved with the bloke that drowned passed away about 2 minutes before sea rescue arrived, so minutes really do count.
Arguably if you activate it from a boat that will come to where its pinging from but they also like to know what type/size/colour boat you are in to make it a bit easier.
And for what it's worth keep your PLB somewhere really accessible, ie somewhere really annoying, lots of boats sink with the PLB/EPIRB safely tucked away in a locker with the PFD's...