Why do the 'Sent' push notification numbers look different in the Journey statistics, the Push Notification dashboard, and the Detailed Statistics?

The 'Sent' figure is measured at different points of the pipeline in different screens, so small differences between them are expected. Here is what each place counts.

• Message statistics > Performance tab (Statistics > Message history, then open the message) — SENT is the total number of notifications Pushwoosh handed to the push gateways (APNs, FCM, and so on) for all targeted platforms. The same tab shows DELIVERED, OPENED and ERRORS, with a per-platform breakdown; the platform values sum up to the totals.
• Journey canvas / per-element statistics — open the journey, hover a message element or enable Show Metrics, then double-click the element for details. Here the number reflects successfully processed sends for that step: gateway rejections (for example Unregistered invalid tokens) are counted as Drop-offs instead, and users skipped for lack of a suitable device are reported separately. That is why a journey step can show fewer sends than the message-level SENT.
• Recipients — a subset of Sent that excludes devices which opted out of push (the Push alerts enabled tag set to 0). If a screen shows Recipients, expect it to be lower than Sent.

In short: message statistics report the send attempts made to the gateways, while journey statistics report the attempts minus known invalid or skipped devices. To reconcile a specific campaign, compare the ERRORS breakdown in the Performance tab with the Drop-offs shown on the journey step.