Śūdra means he must find out a master. A master. Paricaryātmakaṁ karma śūdra-karma svabhāva-jam (BG 18.44). Śūdra's business is to find out a master. Just like a dog: a dog must find out a nice master. Otherwise it is a street dog; its condition is not very good. Similarly, a śūdra means he must have a nice paying master. Otherwise his life is at risk. So if you consider in that way, the śāstra says, kalau śūdra-sambhavaḥ.
In this Kali-yuga, everyone is a śūdra. You hardly find a real brāhmin or real kṣatriya or vaiśya. Because they are after service. In the śāstra it is said that a brāhmin, if he is in difficulty, he may take the profession of a kṣatriya or up to a vaiśya, but never take the business of a śūdra, like a dog. That is prohibited. And nowadays we are claiming to become brāhmin and going here and there with application, "If there is any vacancy, sir?"
So these things are topsy-turvied. Simply it has become a farce. Actually if we want to establish Vedic civilization, then we must follow strictly the principles of Vedas as it is described in the Bhagavad-gītā. And if it is practiced, then daiva-varṇāśrama-dharma. That is required.
Daiva-varṇāśrama-dharma. There must be the four division. Just like we have got four divisions in our body: the head division, the arm division, the belly division and the leg division. The leg division is the śūdra, the belly division is the vaiśya, and the arm division is the kṣatriya, and the head division is the brāhmin.