The high number of early British exits can, in part, be explained by some tough draws, with six coming up against seeded players.
Although he may have lost, Samuel delighted the home crowd in a thrilling five-set match against Czech 15th seed and French Open semi-finalist Jakub Mensik.
The 23-year-old wildcard, at a career-high ranking of 123 in the world after reaching the Eastbourne semi-finals last week, recovered from two sets to one down to take Mensik to a 10-point match tie-break.
Samuel broke first in the deciding set, and reignited hopes of an upset by breaking back to level at five games apiece, but eventually lost 5-7 6-3 6-3 3-6 7-6 (10-7).
Fellow debutant Wendelken, ranked 202nd in the world, clinched the first set against French world number 75 Valentin Royer in a 4-6 6-3 6-3 6-3 defeat.
Harris also managed to take a set off Russian 19th seed Karen Khachanov but ultimately fell 6-3 5-7 6-3 6-3.
Pinnington Jones played just five games after returning to complete his match against American 28th seed Brandon Nakashima, losing 6-3 7-6 (7-5) 7-5 after trailing 4-3 in the third set when play was suspended late on Monday.
In the women's draw, Boulter also fell at the first hurdle as she lost 6-2 6-4 to Italian teenager Tyra Caterina Grant.
It is the first time since 2017 that Boulter has lost in the opening round at Wimbledon, and her first defeat by a qualifier at a Grand Slam.
It comes just 18 days after she achieved the biggest win of her career by ranking, when she defeated world number two Elena Rybakina in a stunning performance at Queen's.