Yes, that’s a normal thing. But it is not all the coins that has a price relationship with Bitcoin, a lot of them can be entirely on a different route. You just say this because you have only been looking at coins like Ethereum, Stellar, and the rest of them that has a close price relationship with Bitcoin. If you’re looking at all the coins in the market, you will see that it is not all of them that would usually increase in value when Bitcoin does, so they are different.
Bitcoin might be going up, and these you’d notice that these coins will mostly be stable or losing their value as investors moves over to the bullish ones . When Bitcoin becomes bearish or stable, these coins will start doing better.
You are right with that. I have seen a lot of alts that are not following the path of bitcoin. And you know what, most of them are those pump and dump coins.
Because the movement of their market depends on the team itself or investors of their project. So they don't care what's going on with bitcoin, as long as they are getting their goal of pocketing as much money as they can. But for most established alts like ETH, LTC and other top 10-20 coins, you will observe that their trend behavior follows btc movement.