I'm not kidding. Volcanoes and converging plates push mountains up, and mudflows and rain tear them back down, bit by tiny bit, over thousands of years, until they are flat. It would be like living on a really huge porcupine. Little hills and big hills and mountains would be just everywhere. But erosion and mudflows pull down the mountains, and make room for new ones.
Geology is just one big cycle after another.
Earthflows are mudflows that aren't as wet. I bet you could have guessed that. The avalanches you are have probably seen are on TV, and involve mountain climbers on Mt. Everest, or people who have been in a plane crash in Alaska and are attempting a thrilling escape. The truth is, the most fatalities in avalanches occur in Colorado, and Coloradans are very concientious about landslide safety. Anyone worth his or her snow shoes would always be sure to check landslide conditions before he or she went out skiing or hiking in the middle of the mountains.