Nomura Instinet analyst Romit Shah downgraded Tesla (TSLA) to Neutral from Buy and cut his price target for the shares to $300 from $400. The electric carmaker closed yesterday up $22.26, or 8.5%, to $285.50.

In a research note titled “No Longer Investable,” Shah expresses concern that the “erratic behavior” of CEO Elon Musk will taint the Tesla brand. Consumers are fickle and could become scared about buying a Tesla if they believe the company might not be around long-term, Shah tells investors in a research note. Shah, who admits to being one of the most bullish analysts on Wall Street since initiating the stock in October of 2017, still believes Tesla could grow to be a much larger company.

The analyst, however, prefers to move to the sidelines pending potential changes in management.