2006 Chevrolet Malibu - Why this change?

When I try to start my car after it has been sitting for a while (usually overnight) it takes two or three cranks for it to start. After only a short while on a restart it always starts on the first crank (almost like it has “warmed up”}. Does this indicate the starter is going bad or is it something else?

The starter is fine. Either your fuel pump backflow valve or an injector is leaking. Try some fuel injector cleaner in the gas tank as a first try. If it is an injector, that may clear it up. It isn’t critical so if the pump has lots of miles on it, it may make sense to proactively replace it.