Because at the beginning of the miners are still few, so the hash rate and the difficulty is less.
When more people learn about the coin, it will become unprofitable for mining on laptops.
There may be a situation that the new coin will sink into oblivion. Then all my mining will be useless.
You can also buy a coin that will sink into oblivion. You can buy ICO tokens that will lose the price to zero. Crypto is risky. Mining coins without risk requires an ASIC or GPU, but not a laptop.
From my experience, even gaming laptops are very much inferior to stationary solutions of past generations.
And yes all because laptops going in thin case and it is very difficult to make normal ventilation for a powerful configuration.
CPU temperature is near the limit, but does not exceed the limit. This is when all cores are fully loaded. And on a laptop, mining on the GPU is useless. GPU installed in laptops are much weaker than conventional GPU. But the CPU in laptops can be used for mining. Therefore, it is necessary to choose coins that can be mined only on the CPU.