Consider the following simple expression in SQL Server SSIS, where a variable is built with the following expression containing a conditional operator:
"Preamble " + @[$Package::myParameter] == "" ? "" : "Middle Text" + " The End"
The logic is simple. If myParameter has a value, the "Middle Text" bit will be shown. If there is no value, then it will show nothing. While the conditional seems to work fine, I noticed that any text/expression I have prior to the operator is simply ignored. In this case, the "Preamble" text is never shown regardless if the boolean check gets to TRUE or FALSE.