Wall Street is still crushing Apple (AAPL). The stock is now deep in bear territory, down roughly 25% from the record high it hit just ahead of Apple’s record-breaking iPhone 5 launch in late September. Apple shares closed down more than 2% at $525.62 on Thursday, pushing Apple’s market capitalization below $500 billion for the first time since May. The company just posted a record September quarter, it’s guiding for a record holiday quarter and some analysts expect Apple’s performance to keep soaring. So what’s going on? According to one market watcher, “people overbelieved in Apple.”

“Investors had believed Apple would take over the world, management was flawless, its products were in infinite demand and competition couldn’t make a dent,” DoubleLine Capital portfolio manager Jeffrey Gundlach told USA Today. “People overbelieved in Apple.” DoubleLine is currently short Apple shares.

USA Today’s Matt Krantz lists a few key items among the reasons for the steep decline in Apple’s stock: “Worry about changes coming with investment taxation,” “realization that losing its visionary founder isn’t something to be ignored,” and “profit compression” that is likely to hit as costs rise and competition increases.

Apple’s stock now sits at its lowest level since February and while Apple bulls are looking for a rebound to start any day now, many aren’t convinced the current dive has bottomed out.