What does flag:type=signal mean? The documentation is self-contradictory and the history behind it raises even more questions.
The original approved proposal for man_made=flagpole included this clause and illustration:
Some flags are signals (at beach for swimmers).
However, that doesn’t appear to be a safety signal of any sort. It’s a Blue Flag, which advertises a tourism certification.
In 2017, flag:type=signal was first documented using the same Blue Flag but a less coastal definition:
A flag that marks a spot (like guard towers or places for first aid)
Since then, the definition has changed slightly:
Flag that marks a guard tower, first aid station, etc.
Marking the location of a guard tower or first aid station is very different than signaling a hazard to swimmers. Confusingly, the image that now illustrates the tag shows two distinct flagpoles: one flies a Blue Flag and the other flies lifeguard flags:
A Blue Flag doesn’t necessarily have anything to do with a beach or mark the location of a lifeguard tower:
Meanwhile, the 213 existing occurrences of this tag represent a variety of things: a flag in the middle of a field, a fake flagpole camouflaging cellular “signals” (hah), a boundary marker that served as a navigation aid to the Wright Brothers on some of their first flights, a flagpole for race signals during regattas, and finally a pole for lifeguard flags (nicely signposted as such).
A couple years ago, @LivingWithDragons asked how to map a storm warning tower or other post for safety flags, since the documentation made it sound like flag:type=signal was for something other than signals.
What should flag:type=signal represent in the context of the other flag:type=* values? Does it even represent a single concept, or should we split it into less ambiguous values?
On the other hand, the 
I do think there’s a whole range of warning-related flags that we’ve left unencoded despite being common reasons to erect a prominent flagpole.
