Tesla experienced a 13% decline in vehicle sales in the first quarter, marking its worst performance since 2022, with deliveries totaling 336,681 vehicles, falling short of analyst expectations. Factors contributing to this slump include an aging vehicle lineup, increased competition, and backlash against Elon Musk's political actions. Despite deep discounts and incentives, the company faces ongoing challenges, including factory downtime and market share loss to rivals, while investor sentiment remains volatile amid speculation about Musk's future in government.