It's the experience of sitting under the blazing afternoon sun, doing your best to build a grand structure that only exists somewhere in your imagination. You may have to make adjustments to your artistic plans along the line for reasons of practicality. You will probably need to rebuild exterior walls as the drying sand crumbles continuously before your eyes. With the rising tide, micro-tsunami's threaten to wash up and destroy key aspects of what you have already accomplished, but you continue to work on undeterred in search of your ultimate goal.
If you are very lucky, you stand a chance that your sandcastle will make it to completion and survive the forces of nature just long enough to be observed by a few public bystanders strolling along the beach. But you have known all along that the result is temporary and transient. For the amount of effort you have invested in the activity, the end product has little or no practical value.
So why do we build sandcastles?
I think it's the adrenaline rush we get if we succeed. A little momentary elation is worth all of the sunburn.
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