Your SSD has 512GiB flash. That are 549755813888 Bytes. Available for usage are 500 000 000 000. So you already have 10% more flash than you use. If you create a 480GB ~ 450GiB partition then this will leave about 20GB free space. You may later use it as swap, extend the existing data partition or something else. Free space at the end is always better than in front and it won’t matter for swap or something because the speed is the same.