Why do I need to burn my large candle for more than 1 hour and less than 4?Updated a year ago

If you burn for less than one hour the wax may not be melted all the way to the outside of the candle. Once this happens the candle can form a pattern of tunnelling which leaves unmelted wax around the edges, may reduce the overall fragrance throw and eventually may drown the wicks so the candle will not stay alight. If you burn for longer than four hours, the candle wick can become quite long and may fall onto the side of the glass, or heat the glass up.