You really shouldn't run out the door during and immediately after (as in, as soon as it seems to have stopped) large earthquakes. The building, structurally, will most likely be fine (unless it's a truly massive one in an area that doesn't get massive earthquakes normally), however the facade and whatever else is on the outside of the building probably won't be. Think roof shingles, billboards, windows, planter boxes, trees, powerlines, antennae...

Plus you'd be surprised how hard it is to even stand straight during particularly strong quakes yet alone walk/run, there's no possible description I can give to explain adequately how strange it is to feel the ground underneath your feet shaking violently, especially in buildings.