The obligation is to make ghusul when you are sexually impure due to ejaculation or intercourse. However, a Muslim should be always clean and smelling nice! If you are this clean without showering, this is fine.

We know that cleanliness is highly important in Islam, and there are punishments in grave for unclean people. Hadith says, not taking water after urinating is an example of uncleanliness. Assuming, I didn’t have any sexual discharge, do I need to shower everyday?In other words, do I become an unclean person just because I shower 4 days/week?