As others have pointed out, most misdirections can be better understood by tapping the screen to get the overview screen to see if your Garmin is actually telling you to do what you think it is, or if it has the compass points wrong momentarily. A lot of times, when it tells you to get on 35N, for example (this seems to happen more when there are service roads that parallel the interstate ), it seems to do it because you have to get on that service road to get the ramp for 35S and to go up to the next overpass to go over for 35N, and I bet it's been put into the Garmin database wrong for that interchange. When that happens, at least on mine and I sense it's wrong, I tap for the overview screen and see what it really means.
When it tells me to get off a ramp only to make me cross the street and get back on, it most always is because it is a fraction shorter to do so, which seems silly, but is what the unit has been told to do.
Mine also usually says the wrong direction for the first turn of a trip, which seems to be widespread. Mostly, these little glitches are easily overcome as you get used to your new Garmin.
Against the Garmin directions, I pulled into a new shopping area one time (that definitely was not in the maps yet) to cut the corner of a notoriously busy intersection, and my Garmin went nuts, almost interrupting itself in a flurry of "recalculating", "driving off-road" and "when possible make a U-turn" messages. My passengers and I were in stitches.
An amusing thing to do with your Garmin is to alter the text to speech file with a hexadecimal editor. Mine now says, instead of "lost satellite reception" when entering a tunnel or in concrete canyons, in her cute Australian accent "It's fooking dahk in here!". When about to enter a roundabout or traffic rotary, she says "What is this, New England?". When I make a turn to early or other mistake and she would normally say "recalculating" she says "alrighty, let's try it your way...".
And when at my final destination, she says "Yo, we be at _____"
