If you have a trigger to determine host being down that includes an or statement dependent on data, the trigger fails to actually evaluate if the host in in fact down.
In this example, the expression includes a check for nodata with or operand to also check if the returned data is of a certain value.

The expectation is that IF there is no data for the designated period of time, OR if there is data and it's of a value x, then the trigger will fire.
However, the trigger is ignored completely and listed as OK due to being unable to evaluate the expression as there is no data.

That would be expected if the operand was AND, but it's OR, so it should be returning that there is a problem because there is no data.
This means I have to have two separate triggers instead of one, which makes making maps more complicated as I have to layer trigger icons in some way because you can't put multiple triggers on an icon.

While not a blocker, this issue takes me from easy to extremely difficult when it comes to making a map based on a complex trigger that should tell me under a number of conditions if a host is in a "down" state.