Is a 100 watt amplifier Loud?

Could you please clarify for me, is a 100 watt amplifier considered loud in terms of its output volume? I understand that wattage is a measure of power, but how does it translate to the loudness of the sound produced by the amplifier? Is there a direct correlation between the wattage and the loudness, or are there other factors that come into play? Additionally, what would be considered a loud amplifier in general, and how does a 100 watt amplifier compare to that standard?