Explain me why quill rain is bad in late game builds

Hi, I'm a casual player and kinda new to late/grindy game. So the thing is, every build telling me that quill rain is great for levelling but when you have the currency you buy some other rare bows with bla bla stats.

The problem here is quill rain is best bow. The reason I'm thinking this way is:
in my toxic rain raider build dps tab says with quill rain I have 1.220 DPS. okay
when I wear the rare bow I got it says I have 3.200 dps... it triples the damage its HUUGE
BUT there is problem, it is so slow that either I die while trying to hit, or I have to run away without hitting.

With quill rain in 1 second I leave millions of toxic pods in ground and *dash* *dash* away from danger. So, that quill rain 1.220 dps becomes better than a 100ex priced +2 level gem, +chaos multiplier rare bow.
When you combine that quill rain with onslaught it goes BRRRRR RA TA TA TA TA melts everything. the low dps and %30/%40 less damage thing becomes nothing.

So tell me, why everyone keep saying buy a rare bow, leave quill rain, its bad.

If I take any attack speed from either items or passive tree, I lose something else such as resistances, life or damage. also I don't have 10000ex to buy a perfected build, sooo??!

If your characters weren't private I could say more, but the short version is: quill rain is double attack speed 30% less damage, so you take 70% of your normal damage twice = 1.4 times normal damage. You replace it only when you get a bow that provides bigger damage bonus than 40%, which end game bows can. That ofc applies to skills that scale well with attack speed, like toxic rain or explosive arrow.

Anyway, you should get enough attack speed from ascendancy if you play Raider (onslaught path) or Deadeye (tailwind path), before you get those ascendancy points ofc your attack speed will feel slow.

You should also pick some attack speed from tree like Master Fletcher line, Finesse - these are always on your path and worth picking, and potentially Harrier, Coordination and Farsight, depending whether you path nearby or not.

You don't need 1 million exalts but standard equipment for toxic rain would include also crafting attack speed on gloves and quiver (assuming you don't use uniques, however Maloney's Mechanism I think has attack speed too), using a cluster jewel with Unholy Grace (literally only good suffix you can easily roll on a big cluster, the other one being explody mod but it's super rare) and rare jewels like viridian with attack speed / attack speed with bows.

Common utility skills include blood rage and vaal haste, which provide more sources of attack speed.

You can keep quill rain until red maps really. A bow that will beat it for pure toxic rain build costs 12-20ex to make (not 100ex don't get scammed by overpriced bullshit), so you should transition once you have currency for it, which also means rest of your gear would be upgraded by then.

Also do not spec resistances on the talent tree unless the node provides something else useful like freeze avoidance or max res. Just buy a couple of resist items off the market, you can get decent ones for like 10c each.

Also if you play caustic arrow with arrow nova, quill rain will lower its damage and it's gonna be really poor. But if you clear with toxic rain alone you'll be fine.

P.S. Last thing I forgot to mention, once you get a lot of attack speed you will also have problem sustaining mana (you can have like 7-9 aps with quill rain), so you have to solve mana problems, and also swapping to bow that provides bigger damage per 1 toxic rain allows you to deal similar or better damage for less mana per second.

You answered your own question, it has shit dmg compared to a cheap rare bow. If you stand still to shoot for 1s with your rare it does as much dmg as standing still for 3s to shoot with quill rain, basic math.
If you are struggling with standing still for 0.4s or whatever it takes to shoot with your standard thicket bow, you have other issues with your build. Also use mirage archer, then you can shoot while moving and its unironically a huge multiplier for any fight where you have to move a lot.

If you don't like having to stand still to deal damage, do what I do and use totems.

It just a leveling bow , any end-game bow will beat it

The bow has (had) a niche on ailment DOT build but i think those build can still use better rare bow