Comment by namibj

First reaction to warning tone should always be to (safely!) stop and assess.

Considering that the persons involved can't be expected to not be deaf, or functionally so via e.g. headphones, and thus you always have to be able to brake anyways. Running onto a driving lane (be it bikes or cars doesn't matter) without looking especially if the direction you didn't look just gave an audible warning is always reckless.