The 21% rise in Ambarella's stock price is attributed to its strategic growth in key markets like IoT, AI, and automotive, which are currently high-growth sectors. The company's innovative product launches are likely contributing to this positive trend. However, the presence of strong competition, potential regulatory hurdles, and seasonal business fluctuations could temper future gains. Overall, the positive growth in these sectors suggests a likely upward trend in the short term, but investors should be cautious of the mentioned challenges.