Why does RSA encrypted text give me different results for the same text

A secure RSA encryption is implemented with an appropriate padding scheme, which includes some randomness. See PKCS#1 or OAEP for more details.

The RSA encryption encrypts message padded with '0's and and a string of random bit. In the process, the random string is "hidden" in the ciphertext by cryptographic hashing and XORing. On decryption, the RSA decryption recovers the random string from the ciphertext and use it to recover message. This is why you get different result with openssl rsautl for the same text message.