Not on every take off - on some there will only be one V1.
That's called a balanced field length where V1 go = V1 stop.
By using Flex Thrust method, you can alter the performance, for the given runway length, terrain etc. so you end up with V1 go = V1 stop.
There will be a maximum temperature allowed for flex calculations, so if you reach max flex on a very long runway with no obstacles, you will generate a range of V1 go & V1 stop.
Our performance software allowed us to look at the V1 range with different flex figures.
I agree with fireflybob. Sometimes it's better to take the problem into the air and sort it out, sometimes it's better to stop - but you won't know which one was better until you've had tea and biscuits. V1 in the middle seems a very good compromise to me.