What happened Shares of electric-truck maker Nikola (NASDAQ: NKLA) declined 5% on Thursday, as of 1:20 p.m. EST. The drop is a fitting end to a troubled year for the company. So what The stock has been in a general downtrend over the last month after an agreement with General Motors was announced and was a much smaller deal than had originally been indicated. Shares took another hit last week after Nikola said it was backing out of a deal for an electric garbage-truck fleet for Republic Services. So what does that have to do with today's drop? It's likely that some financial managers are getting it out of their portfolios for the end of the year. Nikola Tre semi truck. Image source: Nikola. Now what Nikola got a big black eye this year after a short-seller report exposed some company issues, forcing founder and executive chairman Trevor Milton to resign. Money managers probably don't want to share that black eye with clients that see they own shares that have dropped almost 80% in the second half of the year. Investing is about looking forward, however, not back. Nikola will need to prove its plan to bring battery-electric and hydrogen-electric trucks can be successful. It will require concrete, appropriate cost numbers for hydrogen and a fueling network to be established. And first the company will need to show it can make, and sell, battery-electric trucks. That's the data investors looking ahead need to watch for next year. 10 stocks we like better than Nikola CorporationWhen investing geniuses David and Tom Gardner have a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.* David and Tom just revealed what they believe are the ten best stocks for investors to buy right now... and Nikola Corporation wasn't one of them! That's right -- they think these 10 stocks are even better buys. See the 10 stocks *Stock Advisor returns as of November 20, 2020 Howard Smith owns shares of Nikola. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.Source