Bottom line; let’s quit bandying words here:
What is the result to a person’s soul, if they do NOT believe the wafer and wine are Jesus’ body?
As to your question, why don't you let Jesus Christ answer?
53 Jesus said to them, “Very truly I tell you, unless you eat the flesh of the Son of Man and drink his blood, you have no life in you.
54 Whoever eats my flesh and drinks my blood has eternal life, and I will raise them up at the last day.
55 For my flesh is real food and my blood is real drink.
56 Whoever eats my flesh and drinks my blood remains in me, and I in them.
57 Just as the living Father sent me and I live because of the Father, so the one who feeds on me will live because of me.
58 This is the bread that came down from heaven. Your ancestors ate manna and died, but whoever feeds on this bread will live forever.