Why do people on Star Trek bother going to the transporter room if they can just beam out from the bridge

Yeah, I've always assumed (In TOS, you don't need to assume, they actually stated that intra-ship beaming was dangerous) that there are too many power conduits, shield generators and other interference producing things dotted around the interior of the ship, which is also made of the most ridiculously impermeable metals... So, doable, but even with the staggeringly precise technology of TNG... just a hair more dangerous than beaming from a transporter room.

I've never bought into that theory. I don't remember the exact quotes, but language on the Original Series seemed to indicate that it was converting the transport-ee into energy and firing them through a beam and re-assembling them on the other end of the beam. I suppose, arguably, that process is killing them, but for purposes of in-universe logic, I don't think it's true.

While that may be theoretically true, we don't see it on the shows. Without a malfunction (usually caused by a Strange Entity) or some other kind of noticeable interference, the transporters are accurate and run like Swiss clocks. It's a good explanation, I suppose, but they're never nervous about it and they never seem to bring it up as a problem when they need somebody beamed directly to/from a non-transporter environment. "We're beaming directly to sickbay!" is never a problem, for instance.