I would have thought technically it's the sort of thing that someone would have normally been sent to do, but it's a while since I saw Generations so I can't recall all the details of why Harriman was going to go (and thus why Kirk had to swap with him).
Beyond the script needing him to, of course.
'If the Apocalypse starts, beep me!' - Buffy Summers
'The sky's the limit.....' Jean-Luc Picard, 'All Good Things'
courtesy of Saquist