The cycle count only matters when it gets near 1,000 cycles which indicates the battery is at end of life. A laptop plugged into a charger most of the time will not increase the cycle count, but the battery will age & degrade over time. A low cycle count does not necessarily mean a good or healthy battery.
Option-click on the battery icon to see the condition of the battery. Anything but "Normal" or "Good" means the battery is either wearing out or has an internal fault. You can also run the Apple Diagnostics to see if there are any hardware issues.
If you use Coconut Battery it will tell you what percentage of capacity is left from when the battery was new. This is a better indicator of health if you want a numeric percentage. Apple just uses "Normal" for over 80% capacity of new, "Replace Soon" for X% (I don't know the value for "X"), and "Replace Now" for Y% (again I don't know the value for "Y"). Basically "Replace Soon" means the battery will still give many people a reasonable runtime (at least several hours), but "Replace Now" may only give you an hour or less of runtime.
4 to 6 hours of runtime is not unreasonable for a battery even if new depending on the system load. If you have a third party battery, then all bets are off on how the third party battery will perform since the quality of most third party Lithium-ion batteries is extremely poor.
