True...but that's why its important to have a room lined up...and to just chill for 24 hours...
Anyone who "does" Athens in two days...or Rome in 36 hours...is seriously missing the point of travel...
Any city worth visiting is worth at least a week... The only problem is that after a week...you really start to get the hang of a place... And then you have to move on to the next city...and start all over again...!
Well...travel can be a bit stressful...and often it is "rewarding" only in retrospect...not as its happening...
But at least you can try to enjoy it...! LoL...