At least they didn't accidentally beam them down to a planet without bothering to check if the planet was even still there.
Well, there were no paranormally powerful children ordering them to do so this time around...
A number of unpredictable things can happen when someone removes the part of the transporter responsible for scanning what's there and neglects to tell the transporter chief not to use the transporter while it's removed.
One might note that this was basically the first time, and the only time for a while, when two active ends were involved in a transporting process. That is, there was a "signal" coming from Earth that the sending end was expected to "boost", but nevertheless the machinery at the Enterprise
end was also messing with the process.
Presumably, the process would have gone without a hitch had Rand not activated the Enterprise
machinery at all. Which may be why nobody bothered to tell her that her machinery was down for repairs.
Although that's exaggerating quite a bit: the machinery wasn't really "down". Another piece of machinery somehow relating to it suddenly blew a fuse just seconds before the transport. At which point our heroes immediately
informed the transporter room. A tad too late, of course, but c'est la vie. I don't really see the supposed incompetence here.