Quite simply, women's fashion is more complicated, and so women have many more shoes to choose from. A "core" set of shoes, for women, in order to stay trendy, would probably be:
- Casual sandals
- Work sandals
- Casual flats
- Work flats
- Work heels
- Party heels
- Winter boots
- Gym shoes
- Shower sandals
Whereas for men it would probably be
- Work shoes
- Casual shoes/gym shoes
- Shower sandals
If you're going to preface this list with "in order to stay trendy" you should keep up with male fashion trends, and from this list we can glean that you don't, fair EJCC. A man needs far more than three pairs of shoes to be trendy.
First of all, "work shoes". That depends on where you work. "Business" attire requires at least two pairs of shoes: black and brown leather shoes, usually of the Oxford style. "Business casual" still implies a leather shoe although a loafer may be acceptable. ("Business casual" is a nebulous term that can vary substantially from company to company, let alone city to city; what may be "Business casual" at one office may be considered full-on "casual" and completely inappropriate in another, or vice-versa.) No matter whether he wears a suit and tie or merely a collared shirt a trendy man will have
at least two pairs of "work shoes".
Blue-collar workers often require a pair of steel-toe and sole boots. So do professionals in certain fields, e.g. engineers and geoscientists who might have to visit "site".
"Casual shoes" run the gamut from loafers, less formal slip-ons (e.g. boat shoes), canvas shoes, sneakers/runners/gym shoes... A trendy man will have at least two pairs of casual shoes. A particularly fashionable man would have several pairs in an assortment of colours, and may also have one or more pairs of sandals.
A trendy man will also have at least one pair of sneakers/runners/gym shoes for exclusive use when exercising and/or playing sports, in addition to the ones he may have as mere "casual" shoes.
The number and style of boots a trendy man owns will vary based on his location and vocation. In a snowy climate he may have a dedicated pair of winter boots. In a more moderate climate he may have only a pair of leather chukkas. In a rainy one he will almost certainly have a pair with a rubber sole so as to not subject his leather-soled business or business-casual footwear to damage.
In summary a trendy man will have:
- at least two pairs of work shoes, plus any heavy-duty footwear as required
- at least two pairs of casual shoes
- gym shoes
- additional weather-appropriate footwear (winter boots, rain boots, etc.)
That's
at least five pairs of shoes, and the final total can very easily be double that.
(And no trendy man owns "shower sandals"...

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