Monday saw a strong session on Wall Street, with the Dow Jones Industrial Average rising nearly 100 points and building on gains from late last week. Sentiment among investors seemed to regain its footing from the rampant pessimism that prevailed during the final month of 2018. Yet some stocks failed to join the party, and PG&E (NYSE:PCG), Maxar Technologies (NYSE:MAXR), and Medtronic (NYSE:MDT) were among the worst performers. Here's why they did so poorly.

Worries return for PG&E

Shares of PG&E plunged 22% as new speculation arose about the possibility of the California utility company filing for bankruptcy. In the immediate aftermath of the latest string of wildfires to hit the Golden State, PG&E initially fell sharply on fears that it would be held liable for at least part of the billions in damages that resulted. For a while, positive comments from various interested parties restored some confidence, but now, shareholders are looking at changes on the board of directors and comments about a possible state takeover of the utility as being more likely -- and potentially catastrophic for owners of the stock.

Check out the latest PG&E earnings call transcript.

Two power lines with multiple cables hanging between them, at dusk.

Image source: Getty Images.

Maxar shares fall to earth

Maxar Technologies' stock lost more than 30% of its value in the wake of its report that its WorldView-4 imaging satellite had suffered a critical systems failure. According to the space-based technology specialist, Maxar's satellite experienced a failure in its control moment gyros, and as a result, the satellite lost its ability to gain enough stability to collect imagery. Maxar has tried to correct the fault, but it now believes that WorldView-4 won't be recoverable. With a potential write-off of $155 million for the company, Maxar shareholders aren't happy about the loss and the impact on future growth.

Check out the latest Maxar earnings call transcript.

Medtronic warns on results

Finally, shares of Medtronic finished over 6% lower. The medical device giant gave a presentation at the JPMorgan healthcare conference, in which it gave guidance for earnings over the next couple of years. Despite fiscal 2019 projections that were generally in line with what those following the stock had expected, fiscal 2020 earnings guidance left something to be desired. That disheartened short-term traders, but Medtronic's solid long-term prospects should lead some to believe the stock represents good value at current prices.

Check out the latest Medtronic earnings call transcript.