There are some factors that need to Notice before Investment on any Altcoins.
Market cap of that Coin
24h volume of that coin.
Maximum supply of coin
Blockchain Technology that Coin is using.
Globalization
Community behind that Altcoin
Whitepaper
Liquidity
If I missed anything then include this in this Topic
good list. also you can look which exchanges listed than coin. for good grown up coin in most cases it should be at least 1 of top 10 exchanges.