Most of the users here are regretting not buying at the lowest price of a coin but do you really know at that time that it really is the lowest price of that coin? And Vice-versa...
It is much worse to buy a coin at the maximum price and then wait for years for the price to return to its previous values or sell it at a loss. So, it is better to sell the coin, as OP did and make a profit, than to sell your coins at the lowest price, while losing your deposit.
If people buy more than the maximum price then they are hit by FOMO which eventually buys and holds it with higher expectations after a few years but in the end it becomes a big loss, what I said that I have experienced and of course it is a regret that should not be happen again.
By selling coins that don't need big profits I think it's enough as long as we have set the percentage we set, but they are always ambitious and lose for bigger losses even this often happens.