There's loads of things to worry about if you are a bear such as valuations, China, US yield curve flattening, economic woes in Europe, the recent collapse in freight rates etc. Here is an apt summary of these views from the pro's:
Things to Worry About as a Bear
Seven Mistakes That Lead To Late Payments From B2B Clients
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Inadvertently, even well-established companies might be ignoring best
billing practices that minimize delays in client payment.
18 minutes ago