"I think it's the bottom bracket"

Noise.  Bikes make noise.

I hate noise.

At the shop, if someone comes in with an annoying creak, clunk, click, or squeal, inevitably the first words out of their mouths is "I think it's the bottom bracket".

I think "bottom bracket" is the only component name some people know.

It very well may be your bottom bracket.  It may not.

Bikes make noise.  Lots of noise.

Even well maintained bikes can develop noise...not as likely as non-maintained.
(I'll refrain from future snark from the high horse...today)

Noise can come from anywhere two parts come together. 

A dirty freehub, headset, loose or worn hub bearings, loose pedal bearings, clipless pedal cleats, spokes, nipples, quick releases, frame fittings. saddle, seatpost (obviously can be eliminated by standing). cranks, chain ring bolts, etc, or sometimes even the bottom bracket.

You can see how diagnosis can be a challenge.  Especially in a carbon bike with it's acoustic properties.

Sometimes it obvious, often it's not.
Often a huge time suck down that rabbit hole.

Preventable?
Sometimes...Sometimes not.

It very well may be the bottom bracket.


or not.