Bathing is one of the most vital human ritual and must be done regularly, or on regular basis. Cleansing one's body is very important. Apart from possibility of skin diseases and stinking after a few days, one starts feeling not so good and bathing at once refreshes one's body and mind.
Bathing in summers is fun, but bathing in winters can be a punishment for some (that includes me). Water has inherent quality of a coolant and even warm water can provide relief from cold for only some time.
Bathing should not be a compulsion as much as a fun activity. Many people sing fondly while bathing, and one might even get some useful ideas while bathing (personal experience). Also, since a person is alone while bathing, it could be added to the quality time spent with oneself. :D
Bathing under shower is best, as it requires minimum effort. Bathing under tube well in open is supposed to be exciting, haven't had the pleasure to do so.
Many people start their day with bathing, while some others don't bathe for days (including me). Whatever be the behavior towards bathing, an irregular bather also enjoys bathing.
Bathing is not a compulsory activity and life without bathing isn't much different. But like all the other good habits, bathing helps in maintaining healthy body and mind!
P.S. - Swimming doesn't count as bathing
P.S. - Dipping in holy waters polluted over the years might have reverse bathing effect. :D