Cause america was CHEAP! It was also the same with the cartrage interface connector. While the famicom was flawless with it's start-ups, the NES suffered from issues that would crop up when ever the power button was pushed in. Sometimes the game screen would come up with no problems what-so-ever, other times we'd be fighting with the damn button until the game screen came on. The only way I found to eleviate that problem was to always hook up the game genie. The problem was eventually fixed when the NES was re-released looking kinda like the SNES in design.
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