Speculation is in, conservatism is out as retail investors bid up questionable assets and imaginative financing exploits the public mood. Buyers, beware.

Social media buzzed with excitement on Monday as some beaten-down stocks that retail traders have been buying began to soar. Kohl's, Opendoor Technologies, Krispy Kreme and Rocket Cos. were among the names that posted outsized swings throughout the week.

The market saw a fresh meme stock frenzy this week. While high exuberance can be a contrarian sell signal, sources say the market is still in good shape.