It's not that strait forward, you indeed need to know in more detail what information/answers you need, because if you would simply like some strait forward information to be able to make a distinction on what is better, then you would be on a perpetual endeavor.
They are both great toolsets that perform overall same functions, interfaces are somewhat different but generally everything that one can do in Maya one can also do in 3ds max.
You could go on and on in comparing but it basically comes down to what one personally prefers to work with.
Best go in try them both and feel watt works best for you.
It is good to know what type of work you need to perform the most and see how the different toolsets compare on that (what do they deliver on that specific front)?
For example, if you would be modeling most of the time, then see how the modeling features compare and so on.
But in the end it comes down to what one feels most comfortable with.
One could argue that this or that tool is better but when it does not feel well in hand for a given person then it will not work well for him.
I'm used to work with 3ds max, that toolset feels most intuitive to me so everything I would say would be more biased towards 3ds max.
Vise versa a Maya type would be more biased towards Maya.
The basic take away is that they are extensive toolsets and you can basically perform same factions with them.
If I would be starting from scratch I would probably also consider toolsets like blender, that toolset is free and it has a big community of users and lots of updates, those are also aspects to consider.
If lots of procedural generation is your thing then you would probably best go for Cinema 4D or Houdini, better for motion graphers etc., they are known to have extensive procedural means.
Sorry if this not really helps but probably no one is going to give a strait forward answer on this.
Best break the things you need to know or want to do down to its constituents, work out what information is needed most and work yourself out from there.
I can also say this, the tools don't make you the artist, they are not the decisive factor on that, You can be a great artist on whatever toolset.