Evaluating design is like evaluating food, the two primary metrics being: how nutritious it is and how tasty it is. There are other things you may consider, like the presentation of the dish and the smell, but they are secondary. With design, we have much the same thing in that a product must satisfy its function (i.e. how nutritious it is) and also look pleasant to the eye, or delightful to use (i.e. how tasty it is, though we can combine the presentation and smell here, too). Food that doesn’t taste nice but is otherwise nutritious is not bad, and is definitely preferable to food that tastes nice but is unhealthy, just like we would prefer a design that is ugly but works over design that is beautiful but is otherwise unusable or broken. Good design is one where both of these metrics are at the top, like a delicious and healthy dish.
Immoral design is like a dish made of bad produce that will make you sick through the negligence of the cook to wash things properly and to throw away ingredients gone bad, or junk food that is consciously designed to be as addictive as possible with no regard to it also making you fat and unhealthy. On one side we have negligence, on the other unsavory intent. Negligence is sometimes excusable, that is, when the intent is generally good, though not in the case where its roots lie in a surrender of values, i.e. a designer who makes something merely for money with no regard for the safety and well-being of the people who will be using their products. In some goods, the worst thing negligent design can lead to is an angry customer, in others, a loss of life. In the case of malicious design, the designer consciously treads over moral values for their short term gain, obtaining money in the process but losing not only the well-being of his users but his own integrity, the very thing that shapes meaning in their life.