BOSTON ( TheStreet) -- There's a constant turnover of winners and losers in business, and some face the fate of the proverbial buggy-whip industry: obsolescence.Makers of compact and computer discs, and retailers that rent DVDs and video games (think Blockbuster) are on the short list of industries that may evaporate, and a handful of others, such as soda-pop companies and laundromat suppliers, will endure challenging times. That's according to a ranking by IBISWorld, a Santa Monica, Calif., publisher of industry-specific research and market analysis. What defines their poor prospects are declining life cycles, high competition, weaker consumer demand and technology changes, the research firm said. IBISWorld's rankings also include a weighting for growth potential, economic sensitivity and industry structural risk. Here are five of the riskiest industries as measured by IBISWorld: 5. The recordable-media-manufacturing industry carries the highest risk of any of those ranked by IBISWorld, based on an outlook for sharply declining revenue as consumers switch to online sources for their music and movies. Makers of physical media such as optical and magnetic discs, audio and video tapes, CDs, DVDs and Blu-ray discs are doomed. The industry is expected to record revenue of $7 billion this year, but see annual declines of an average of 3% per year through 2016. The chief competition is from cable TV and video-on-demand services. Imation ( IMN), an Oakdale, Minn.-based manufacturer of data-storage media products and consumer electronic products, is one of the industry's biggest players.