[dyladan]

The span is simply the way the data is modeled. The way the tracing works is it calls a component called a Span Processor on both span start and end. It would be possible to implement a Span Processor that sends span_start and span_end events to your backend without waiting for the span to start.

In terms of crashing and taking a long time to complete, these are problems that are very difficult to solve on the backend as well. Simply having the start event without the end event is not enough info to say for sure that there will _never_ be an end event. For low data volumes and simple use-cases this may not seem like a big deal, but it gets complex extremely quickly.