"Why Do Some Big-Name Series and Authors Decline in Quality?"

Dear Milo,

Is it just me or do some of the best series get worse as they continue? I don’t get why such great writers suddenly get so bad. Sometimes they get so bad that I stop reading the series and I’m disappointed or I keep going but I’m not enjoying myself. I thought writers get better over time. Can writers lose their talent?

Sincerely,

Missing Good Series

Dear Missing Good Series,

It’s not just you. Some series (and writers) appear to decline in quality as they continue to publish. And the more popular the series or writer, the higher the risk that this may happen. But it’s not a loss of talent—which I don’t believe is a possibility; at worst, a writer may get rusty after a significant period of rest or need to pause to flesh out some new ideas. Rather, it’s due to a handful of possibilities, ranging from understandable to frustrating, mostly related to the changes and struggles of the publishing industry itself.

It's not a coincidence that this decline in quality appears to be a newer problem of the last 20-30 years. Or, at least, is becoming more common. (Not that it is common these days, but rather happening more now than it did then.) I avoid naming books, series, or authors in a negative way, so I won’t be providing any examples here. However, it sounds like you already have some series in mind, and plenty more are easy to Google to find out people’s opinions. All I’ll say is this phenomenon can not only affect popular series, but popular authors in general. Also, it appears that no genre is immune. 

So how does this happen? How does a highly recognized author or series suddenly stumble into supposed lesser quality?