Why so some use 360 instead of 365 days to calculate interest?

Some financial institutions use a 360-day year instead of a 365-day year to calculate interest because it simplifies the math involved in interest calculations. This method, known as the "banker's year," treats each month as having 30 days, making it easier to compute interest for shorter time periods. Additionally, using 360 days can slightly increase the interest amount charged or earned over time, benefiting lenders or investors. However, this practice can lead to discrepancies in calculations when compared to the actual calendar year.