Usually beef is safe to eat raw if stored and cut with the greatest care for hygiene, but the trouble is that everytime there need to be no harmful parasites or micro-organisms present, which is unrealistic.
Each time you eat raw beef, you are essentially taking a chance with your health.
Some micro-organisms can kill a person within days, but others may take years to assert a negative effect.
Many parasites (like worms for example) are far from desirable too.
My suggestion is to eat fresh for fruit or vegetables, but cook meat, eggs or fish properly, so harmful bugs are destroyed.