The most common surprise on a 2004-era opening isn't the door, it's the header above it. Builders in that window sometimes used a shorter header clearance than older homes, which limits high-lift track options if you want extra ceiling storage later. That's a conversation to have before you pick a door, not during install.
The other issue is opener compatibility. If the house still has its original opener and you're only replacing the door panel, the opener's lift capacity needs to match the new door's weight, especially if you're moving from a non-insulated to an insulated steel door, which is heavier. Mismatched lift capacity burns out a motor fast.
Weather isn't a major factor for the install itself in this cold-moderate climate band, but it affects timing: a day with ice or heavy rain isn't a good day to have the old door off and the opening exposed, so we build a little flexibility into the schedule rather than force a date that doesn't work for the weather.