I DON'T do muffins. I CAN do muffins, but almost every recipe I try is greeted with the cry "They're OK, but I prefer the muffins you buy". Is it any wonder I don't bother with them?*
I don't know what makes the difference. Are shop-bought muffins really just large cupcakes, and technically not a muffin at all? Is it the emulsifiers and humectants and so on which make commercial muffins light and airy but claggy in the mouth, or a different type of recipe? Do I put in too many chocolate chips, or too much fruit, and make them too rich? Is my son addicted to artificial chemicals and flavourings?
However, muffins are useful. There are inevitably days when even a dedicated cake maker can't find the time or energy to cook, even when there's no cake in the house; that's when I buy muffins. 'Cake' is still available, and in a form not to be sneered at as inferior to what is usually provided.
* the one noble, and definitely notable, exception to this pattern are Dan Lepard's Chocolate Custard Muffins which must be declared the best chocolate muffins in the world, as my son thinks they are better than shop-bought muffins.