A good sleeper is not a child who sleeps for 10 hours without waking up because waking IS developmentally appropriate.
Babies don’t typically have a regular sleep cycle until about 6 months of age. So until this period, it is normal for babies to wake up. A “good sleeper” is one who can put themselves back to sleep when they wake up. People of every age wake up for lots of reasons throughout the night. If they learn early on to put themselves back to sleep, it will serve them (and you!) well.