These are some reasons given here why is my Laptop slow problem happening:
1. Enabled Power Saver mode, which can limit processing power and slow down the laptop.
2. Due to the laptop overheats, causing the CPU to slow down to prevent damage.
3. Old or poorly performing hard disk, leading to slow overall performance.
4. You might open many programs or browser tabs at once. This can slow things down.
5. Malware or viruses can significantly slow down your system.