Why does my scrape stop at the start after doing nothing for a few seconds?

Why does my scrape stop at the start after doing nothing for a few seconds? Actually the result is inconsistent. Once in a while it kicks off. Most of the time it just stalls and then closes without having scraped anything. Any ideas?

{"_id":"leader2","startUrl":["https://www.leadersystems.com.au/"],"selectors":[{"id":"category","type":"SelectorLink","parentSelectors":["_root"],"selector":"#leadermenu [tenciasubcode] > a","multiple":true,"delay":0},{"id":"sub_cat_buttons","type":"SelectorElementClick","parentSelectors":["category"],"selector":"#categories > tbody > tr > td:nth-child(1)","multiple":true,"delay":"2000","clickElementSelector":"#refineproductsbysubcategory button","clickType":"clickOnce","discardInitialElements":"do-not-discard","clickElementUniquenessType":"uniqueText"},{"id":"link_to_single_product_page","type":"SelectorLink","parentSelectors":["sub_cat_buttons"],"selector":"a","multiple":false,"delay":0},{"id":"product_title","type":"SelectorText","parentSelectors":["link_to_single_product_page"],"selector":"h1","multiple":false,"regex":"","delay":0},{"id":"dbp","type":"SelectorText","parentSelectors":["link_to_single_product_page"],"selector":"div.current","multiple":false,"regex":"","delay":0},{"id":"SYD_stock","type":"SelectorText","parentSelectors":["link_to_single_product_page"],"selector":".product-detail-box > div > div:nth-of-type(4) div:nth-of-type(2)","multiple":false,"regex":"","delay":0},{"id":"ADL_stock","type":"SelectorText","parentSelectors":["link_to_single_product_page"],"selector":".product-detail-box div:nth-of-type(4) div:nth-of-type(4)","multiple":false,"regex":"","delay":0},{"id":"BRS_stock","type":"SelectorText","parentSelectors":["link_to_single_product_page"],"selector":".product-detail-box div:nth-of-type(6)","multiple":false,"regex":"","delay":0},{"id":"MEL_stock","type":"SelectorText","parentSelectors":["link_to_single_product_page"],"selector":".product-detail-box div:nth-of-type(8)","multiple":false,"regex":"","delay":0},{"id":"WA_stock","type":"SelectorText","parentSelectors":["link_to_single_product_page"],"selector":".product-detail-box div:nth-of-type(10)","multiple":false,"regex":"","delay":0},{"id":"MPN","type":"SelectorText","parentSelectors":["link_to_single_product_page"],"selector":"a#proddetailsmanuflink","multiple":false,"regex":"","delay":0},{"id":"GTIN","type":"SelectorText","parentSelectors":["link_to_single_product_page"],"selector":"#productdetails > div.information-blocks > div > div.col-sm-7.col-md-8.col-lg-8.information-entry > div.detail-info-entry > div.panel-group > div:nth-child(2)","multiple":false,"regex":"(?<=Barcode:\\s).*","delay":0},{"id":"product_description","type":"SelectorHTML","parentSelectors":["link_to_single_product_page"],"selector":"#proddetailsdescription","multiple":false,"regex":"","delay":0},{"id":"image","type":"SelectorGroup","parentSelectors":["link_to_single_product_page"],"selector":".paddings-container img","delay":0,"extractAttribute":"src"},{"id":"length","type":"SelectorText","parentSelectors":["link_to_single_product_page"],"selector":"div.manucfacturer-link:nth-of-type(7)","multiple":false,"regex":"[1-9]\\d*(\\.\\d+)?","delay":0},{"id":"width","type":"SelectorText","parentSelectors":["link_to_single_product_page"],"selector":"div.manucfacturer-link:nth-of-type(8)","multiple":false,"regex":"[1-9]\\d*(\\.\\d+)?","delay":0},{"id":"height","type":"SelectorText","parentSelectors":["link_to_single_product_page"],"selector":"div.manucfacturer-link:nth-of-type(9)","multiple":false,"regex":"[1-9]\\d*(\\.\\d+)?","delay":0},{"id":"warranty","type":"SelectorText","parentSelectors":["link_to_single_product_page"],"selector":"div:nth-of-type(5) a","multiple":false,"regex":"","delay":0}]}

Maybe you are scraping the page when logged in, but the first selector does not mach anything at the start URL when you are not.

Also it looks like the page requires a slightly longer 'Page load delay' as it is taking it's time to load in properly.

@webber
Where are you reading this from in the sitemap above?

Nowhere, just from seeing how long it takes for this particular site to load up in comparison to an average page.