I hate scale-up. Going from the lab, where temperature is controlled with the twist of a wrist or a few clicks on the keyboard to big hunking pieces of metal, where calling for a temperature change in the equipment is no more difficult than in the lab, but the time to enact that change to occur is now an different matter, one that is a negotiation between the thermal capacities and diffusivities of the heating equipment and also with some convective heat transfer coefficients thrown in for good measure. There is lots of standing around and waiting (and little time for blogging).
Of course, scale-up is necessary as it is the knothole through which entry into all-hallowed production is ultimately achieved with its potential for making the company money. And it also is an source of internal happiness as it means that the bench efforts were successful enough to merit further effort. But I still hate it.