* someone picked java 1.7 because 1.8 is new and she or he wants to let some other suckers find all the crappy bugs in it (remember when 1.7 made lucene crap itself? I'm sure someone got to have some fun times with that, and I'm glad it wasn't me.)
* or she or he chose php because it was fast, easy, and had easy access to charting tools (I dunno if this is true or not) and for an internal dashboard what does it matter...
* I already know how to use it and can get the work done very quickly (always a great reason); there's no such thing as software finished too soon
* the company already has a large codebase in X and I wanted to say in the same language, libs, and deployment tools
I love people who say I like to lag versions a year, because it means they've been burned, learned the lesson, and want to let someone else do the debugging. You'll more likely than not get a strong hire vote from me. As parent said, it's about explaining why you picked something.
Random aside: You should look into Aerospace Engineering/programming. You sound like you'd enjoy that type of development (functional programming, huge amount of docs, huge amount of testing, entirely fault tolerant end to end, etc).