magento2 afterGetPrice plugin catalog rule not working on the final price

    <?php

namespace [Vendor][Name]PluginMagentoCatalogModel;

class Product
{
    protected $objectManager;

    public function __construct(
        MagentoFrameworkObjectManagerInterface $objectManager
        )
    {
        $this->objectManager = $objectManager;
    }


    public function afterGetPrice(
        MagentoCatalogModelProduct $subject,
        $result
    ) {

        return $result + 100;

    }

}