In the pursuit of minimalism, I have experimented with wearing the same style of shirt every single day for more than a month. Famous leaders such as presidents and Mark Zuckerberg have argued that one should not choose a new outfit each day because doing so contributes to design fatigue.
As a man, I believe that a spread collar non-iron white shirt is the ideal piece of clothing for most every situation. A white shirt can be worn with any style of pants. Unbuttoned with the sleeves rolled up, it creates a casual appearance. Buttoned up with a tie and blazer creates a formal outfit.
A well-designed product is versatile and adaptable. White button down shirts are timeless and simple. If you are to only wear one shirt, it is the way to go.