An essential wardrobe proposal can help organize purchases and pairings, but it does not have a universal composition. The number and type of garments depend on work, occasions and personal preferences. A standard list may be of little use if it ignores these conditions.
I propose to start from the frequent uses and the products already available. The review should identify concrete shortcomings, rather than building a new whole solely on the basis of a formula. Maintenance and frequency of use also affect what a person can find practical.
Imagine two clients with very different days. One alternates formal and informal activities; the other uses similar clothing for most of the week. A same selection could work well for the former and create superfluous purchases for the latter.
The result should be verified in use, leaving room for adaptation. An essential wardrobe makes sense when it facilitates real choices and respects personal taste. Counselling can make combinations more legible without turning an aesthetic preference into a valid rule for each customer.