I think one of the key problems is that agencies and bands want to make profit from get go instead of seeing for instance making a club tour (that probably doesn't make any profit at that very moment) as an investment into the future. For instance it might be a very smart move to have a club tour covering most of the European countries with just band members, manager, sound guy, and maybe stylist. And in every country arrange a meeting with local press as well as invite them to the gick.
Also why on earth Korean musicians/idols don't have official international fanclubs so that they could really see where their fans are and in which countries the fandom is growing? Setup that asap with $5 registration fee (in order to keep trolls away) and give them assignments to promote you in their country like requesting radio play. Also make your music available for radio stations in other countries.
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