Still today, people have become accustomed to holidays falling on a certain day of the year, and, certainly for religious holidays, it would be difficult to induce people to change these to other dates of the year. The other modern units of time serve more as a series of placeholders than they do significantly different points in time. For example, each hour of the day no longer has a special significance. People recognize each hour in relation to the other hours, as a continuous series throughout the day, and not as numbers that are important in and of themselves for some religious service. Therefore, the counting of modern units of time has evolved to follow the form of the modern arithmetic counting system.
Seconds are the divisions of a minute.
Each minute has 60 seconds. As each second is basically no different from each of the other seconds of the minute, each number acts functionally as no more than a placeholder. The 60 seconds of a minute are not counted 1 through 60, but 0 through 59. In the same way, each hour has 60 minutes, and these are numbered 0 through 59. The hours of the day no longer have their ancient meanings.