As a general rule of thumb, you're right . . . but exceptions do exist. You should always compare the new vs. late-model-used price:
When we bought my Honda four years ago, very few late-model-used models were available. The price difference between those and brand-new was a little less than $1000. So for that small difference, it made sense to get the new vehicle. We picked exactly the details we wanted, and it cost almost nothing.
On the other hand, when we bought my husband's truck a year ago, he was open to several models, and used models abounded. We saved something like 5-6K by buying a one-year old model. In that case, used made sense.
We made different choices, but I think each was the right choice.