People decide to buy and sell real estate for many, many reasons. The thing all buyers and sellers find is that buying and selling a house is stressful!! 
Buying your first home is super exciting! Selling your house because you got a promotion and transfer to Honolulu is also super exciting (and a great reason to sell)!--and THEN, the reality of the process sets in and the emotional roller coaster starts.
Starting up that first hill is exciting. The anticipation of finding your dream home, or getting a great offer on your home is exhilarating. Checking the Internet, searching for houses, new furniture, decorating ideas and talking to people about moving is fun!
Being prepared for the ups and downs of the rest of the ride is critical! Are you looking at houses you can afford? Do you have a realistic expectation of the value of your current home? Do you understand the time commitment buying and selling require?
Selling your home is hard. Cleaning, packing, staging, decluttering, storing and fixing. It can be very uncomfortable having strangers walk through your home and then dismiss it. Or worse, they like the location but hate the decorating. They love the house, but not your asking price. The house sells faster or slower or for more or for less than you anticipated.
Looking for your next home can be just as frustrating - the outside looks great, but the inside resembles the Brady's house from 1972 - all green shag and orange counters. The house is perfect but next to a thruway. The house is perfect but just outside your budget. The house doesn't look anything like the pictures on the Internet!
A good Realtor, working for you, will explain the dips and turns and unexpected obstacles as they come up. It's not an exact science, but having an experienced rider along can ease some of the nerves!!