When you fetch data inside Angular’s ngOnInit(), the component loads first and only shows data after it arrives — leaving users with an empty page or loading spinner in the meantime. Angular route resolvers solve this by pre-fetching data before the component renders, ensuring the view is fully populated on load. Instead of “load → fetch → update,” resolvers change the flow to “fetch → load,” eliminating flicker and improving user experience. They’re ideal for essential, must-have data (like profiles or product details), reduce the need for loading indicators, and allow for early error handling, resulting in a smoother, more professional application.

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