This is the consequence of information overflow, according to a recent large-scale analysis published in Nature Communications.
The authors evaluated a total of 43 billion tweets and analyzed the top 50 trending hashtags in the world every hour on the hour, from 2013 to 2016. They then calculated the time the hashtags remained popular and found that in 2013, a hashtag remained in the top 50 list for an average of 17.5 hours, but the figure had dropped to 11.9 hours by 2016.
This attention contraction isn’t just a product of the internet. For instance, the researchers analyzed how long certain words and phrases remained fashionable in 100 years of literature made available by Google Books. They found that catchy terms were used in books for an average of six months in the 19th century, but only stuck around for a month by the 21st century.