Why don't most modern calendars us lunar cycles as their foundations?

Most modern calendars are based on solar cycles rather than lunar cycles because solar calendars align more closely with the Earth's orbit around the Sun, providing a stable framework for agricultural and seasonal activities. The Gregorian calendar, widely used today, is designed to keep the months and seasons synchronized, which is essential for planning and consistency. Lunar calendars, while accurate for tracking moon phases, can lead to significant seasonal drift when not adjusted to the solar year. Consequently, solar-based systems have become more practical and widely adopted for everyday use.