Is it 100% flat? Barring that it looks good in the picture.

Yes it’s 100% flat. I would think that the actual line for the seam is more hidden/inconspicuous, no?

Here is a different picture. The veins start on one side, and stop/are nowhere to be found on the other

Interesting. Is this normal? Feels like to have paid 1000s to upgrade our countertops it would flow a bit more naturally. Is this truly normal?

Looks pretty standard/good to me.

"The veins start on one side, and stop/are nowhere to be found on the other"

True enough, but what is your fabricator supposed to do about it please? He plays the hand the slabs dealt him. He can't magically bend or create swirls.

Fabricators are at fault here. Not for their work, but for their lack of setting realistic customer expectations before and during the sale.

You not only picked an estone with movement, you picked a white which is probably the most difficult color to seam inconspicuously.

Hit it with a white Sharpie and forget about it please.

Do you understand how stone/quartz countertop are assembled??? There is nothing wrong with your installation or the seam.

They take the slab and cut into at least 2 pieces that are the depth of a counter top and place them at right angles to one another They is no way possible to make the veining match up when you pay for a slab and turn a corner.

Can you see from my illustration that there is no way to match the veining pattern?????

They can't line up the veins but I've seen better color matches in the gap. Try Joe's fix if your installer won't.

I think it’s fine. But I also understand your frustration. I believe the fabricator and the person who sold you the product should have explain the potential issues and how the deal would be handled. Then you could have decided what to do.

The assumption that home owners know the nuances of quartz fabrication is bad. Many here will say so your homework you should have known etc. But the reality is you don’t know what you don’t know you even need to ask about.

I do think once your kitchen complete this won’t be a thing you notice

It’s a great seam. Seams are NEVER “invisible”.