Can you explain this in simple words? TIA.

Test in Determining Similarity and Likelihood of Confusion in Trademark Resemblance EXPANSION OF BUSINESS RULE -The protection to which the owner of a trademark is entitled is not limited to guarding his goods or business from actual market competition with identical or similar products of the parties, but extends to all cases in which the use by a junior appropriator of a trademark or tradename is likely to lead to a confusion of source, as where prospective purchasers would be misled into thinking that the complaining party has extended his business into the field or is in any way connected with the activities of the infringer; or when it forestalls the normal potential expansion of his business.