The most accurate readings are near the right end of the scale, for two reasons. Any inaccuracy in your reading is a smaller part of the total voltage near full scale, and readings near the left end are likely to be off because of incorrect adjustment of the zero adjust screw. If "extreme right" means past the end of the numbers, you may be off there if the needle hits the stop. On meters with a mirror behind the needle, move to where the needle is in front of its reflection for the best reading.