If we are trading for long term, certainly we need to check only EOD charts. For people who are not short-term swing or intraday traders, there is no need to check intraday charts. However, if our focus is to trade in short-term or if our account size is small to sustain the stop-losses on EOD charts, we need to initiate and exit positions during the course of market hour. That is why there is the need of intraday charts. EOD charts do not provide the same conditions for intraday trading. They may provide some good clue but precise points of entry and exit can be known using only intraday charts.
For example, both 15000 & 15143 were good threshold on daily chart for sensex but purchasing or selling there blindly may cause big losses hence we needed some kind of signal on lower periodicity chart to enter the trade.
Regards,
--Ashish