For those not understanding the fix Vs remake argument.
Imagine you take a dress pattern. Cut that pattern out 4 sizes too big for the dress you need.
Make that dress.
You now can not make that dress smaller by 4 sizes with simple alteration.
The length between the shoulder and the waist is too long.
The length across the back between the shoulders are too wide.
The space between the hip and the waist are too long.
No amount of hemming, or pulling in seems will correct that.
So you have to unpick the dress, lay out the pattern again, and actually cut the fabric smaller and put it back together.
This is why when brides are loosing weight for their wedding days, some seamstresses on the last but final fitting will say "you can't loose anymore weight or this dress will not fit" because they can't alter it anymore, they would need a whole new dress.